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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles, called north and south. Here are some examples of magnets. The north pole of each magnet is marked N, and the south pole is marked S. If different poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

Will these magnets attract or repel? To find out, look at which poles are closest to each other. The south pole of one magnet is closest to the north pole of the other magnet. Poles that are different attract. So, these magnets will attract each other.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles, called north and south. Here are some examples of magnets. The north pole of each magnet is marked N, and the south pole is marked S. If different poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same poles are closest to each other, the magnets repel. The magnets in both pairs below repel. Will these magnets attract or repel? To find out, look at which poles are closest to each other. The south pole of one magnet is closest to the north pole of the other magnet. Poles that are different attract. So, these magnets will attract each other.

attract

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S). Here are some examples of magnets. Their poles are shown in different colors and labeled. Whether a magnet attracts or repels other magnets depends on the positions of its poles. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.

Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S). Here are some examples of magnets. Their poles are shown in different colors and labeled. Whether a magnet attracts or repels other magnets depends on the positions of its poles. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.

repel

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Which property do these three objects have in common?

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification.

Look at each object. For each object, decide if it has that property. Potato chips have a salty taste. The rainbow sucker is not salty. A colorful object has one or more bright colors. All three objects are colorful. A flexible object can be folded or bent without breaking easily. The flip-flops and the silk tie are flexible, but the rainbow sucker is not. The property that all three objects have in common is colorful.

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification. Look at each object. For each object, decide if it has that property. Potato chips have a salty taste. The rainbow sucker is not salty. A colorful object has one or more bright colors. All three objects are colorful. A flexible object can be folded or bent without breaking easily. The flip-flops and the silk tie are flexible, but the rainbow sucker is not. The property that all three objects have in common is colorful.

colorful

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Which of these states is farthest south?

social science

Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map.

To find the answer, look at the compass rose. Look at which way the south arrow is pointing. Nevada is farthest south.

Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map. To find the answer, look at the compass rose. Look at which way the south arrow is pointing. Nevada is farthest south.

Nevada

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Which rhetorical appeal is primarily used in this ad?

language science

The purpose of an advertisement is to persuade people to do something. To accomplish this purpose, advertisements use three types of persuasive strategies, or appeals. Appeals to ethos, or character, show the writer or speaker as trustworthy, authoritative, or sharing important values with the audience. An ad that appeals to ethos might do one of the following: say that a brand has been trusted for many years include an endorsement from a respected organization, such as the American Dental Association feature a testimonial from a "real person" who shares the audience's values use an admired celebrity or athlete as a spokesperson Appeals to logos, or reason, use logic and verifiable evidence. An ad that appeals to logos might do one of the following: use graphs or charts to display information cite results of clinical trials or independently conducted studies explain the science behind a product or service emphasize that the product is a financially wise choice anticipate and refute potential counterclaims Appeals to pathos, or emotion, use feelings rather than facts to persuade the audience. An ad that appeals to pathos might do one of the following: trigger a fear, such as the fear of embarrassment appeal to a desire, such as the desire to appear attractive link the product to a positive feeling, such as adventure, love, or luxury

The ad appeals to ethos, or character, by emphasizing the hospital's established reputation.

The purpose of an advertisement is to persuade people to do something. To accomplish this purpose, advertisements use three types of persuasive strategies, or appeals. Appeals to ethos, or character, show the writer or speaker as trustworthy, authoritative, or sharing important values with the audience. An ad that appeals to ethos might do one of the following: say that a brand has been trusted for many years include an endorsement from a respected organization, such as the American Dental Association feature a testimonial from a "real person" who shares the audience's values use an admired celebrity or athlete as a spokesperson Appeals to logos, or reason, use logic and verifiable evidence. An ad that appeals to logos might do one of the following: use graphs or charts to display information cite results of clinical trials or independently conducted studies explain the science behind a product or service emphasize that the product is a financially wise choice anticipate and refute potential counterclaims Appeals to pathos, or emotion, use feelings rather than facts to persuade the audience. An ad that appeals to pathos might do one of the following: trigger a fear, such as the fear of embarrassment appeal to a desire, such as the desire to appear attractive link the product to a positive feeling, such as adventure, love, or luxury The ad appeals to ethos, or character, by emphasizing the hospital's established reputation.

ethos (character)

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During this time, thermal energy was transferred from () to ().

natural science

A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings.

The temperature of each pizza decreased, which means that the thermal energy of each pizza decreased. So, thermal energy was transferred from each pizza to the surroundings.

A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings. The temperature of each pizza decreased, which means that the thermal energy of each pizza decreased. So, thermal energy was transferred from each pizza to the surroundings.

each pizza . . . the surroundings

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Is Megaptera novaeangliae made up of one cell?

natural science

In the past, scientists classified living organisms into two groups: plants and animals. Over the past 300 years, scientists have discovered many more types of organisms. Today, many scientists classify organisms into six broad groups, called kingdoms. Organisms in each kingdom have specific traits. The table below shows some traits used to describe each kingdom. | Bacteria | Archaea | Protists | Fungi | Animals | Plants How many cells do they have? | one | one | one or many | one or many | many | many Do their cells have a nucleus? | no | no | yes | yes | yes | yes Can their cells make food? | some species can | some species can | some species can | no | no | yes

Megaptera novaeangliae is an animal. Animals are made up of many cells.

In the past, scientists classified living organisms into two groups: plants and animals. Over the past 300 years, scientists have discovered many more types of organisms. Today, many scientists classify organisms into six broad groups, called kingdoms. Organisms in each kingdom have specific traits. The table below shows some traits used to describe each kingdom. | Bacteria | Archaea | Protists | Fungi | Animals | Plants How many cells do they have? | one | one | one or many | one or many | many | many Do their cells have a nucleus? | no | no | yes | yes | yes | yes Can their cells make food? | some species can | some species can | some species can | no | no | yes Megaptera novaeangliae is an animal. Animals are made up of many cells.

no

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The north pole of each magnet is labeled N, and the south pole is labeled S. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The north pole of each magnet is labeled N, and the south pole is labeled S. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.

repel

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Does this passage describe the weather or the climate?

natural science

The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere. Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day. Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures.

Read the passage carefully. Liechtenstein is a small country in Europe with many castles. Liechtenstein has cold, cloudy winters. The underlined part of the passage tells you about the usual pattern of cloud cover in Liechtenstein. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.

The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere. Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day. Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures. Read the passage carefully. Liechtenstein is a small country in Europe with many castles. Liechtenstein has cold, cloudy winters. The underlined part of the passage tells you about the usual pattern of cloud cover in Liechtenstein. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.

climate

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What type of rock is shale?

natural science

Igneous rock is formed when melted rock cools and hardens into solid rock. This type of change can occur at Earth's surface or below it. Sedimentary rock is formed when layers of sediment are pressed together, or compacted, to make rock. This type of change occurs below Earth's surface. Metamorphic rock is formed when a rock is changed by very high temperature and pressure. This type of change often occurs deep below Earth's surface. Over time, the old rock becomes a new rock with different properties.

Shale is a sedimentary rock. Like other sedimentary rocks, it forms from layers of sediment. Material that is eroded in nature is called sediment. Mud is a type of sediment. Over time, layers of mud can build up in places like lakes and oceans. The top layers press down on the bottom layers, squeezing out water and air. Shale forms when the bottom layers of mud are pressed together to form rock.

Igneous rock is formed when melted rock cools and hardens into solid rock. This type of change can occur at Earth's surface or below it. Sedimentary rock is formed when layers of sediment are pressed together, or compacted, to make rock. This type of change occurs below Earth's surface. Metamorphic rock is formed when a rock is changed by very high temperature and pressure. This type of change often occurs deep below Earth's surface. Over time, the old rock becomes a new rock with different properties. Shale is a sedimentary rock. Like other sedimentary rocks, it forms from layers of sediment. Material that is eroded in nature is called sediment. Mud is a type of sediment. Over time, layers of mud can build up in places like lakes and oceans. The top layers press down on the bottom layers, squeezing out water and air. Shale forms when the bottom layers of mud are pressed together to form rock.

sedimentary

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Compare the average kinetic energies of the particles in each sample. Which sample has the higher temperature?

natural science

The temperature of a substance depends on the average kinetic energy of the particles in the substance. The higher the average kinetic energy of the particles, the higher the temperature of the substance. The kinetic energy of a particle is determined by its mass and speed. For a pure substance, the greater the mass of each particle in the substance and the higher the average speed of the particles, the higher their average kinetic energy.

The particles in both samples have the same average speed, but each particle in sample A has more mass than each particle in sample B. So, the particles in sample A have a higher average kinetic energy than the particles in sample B. Because the particles in sample A have the higher average kinetic energy, sample A must have the higher temperature.

The temperature of a substance depends on the average kinetic energy of the particles in the substance. The higher the average kinetic energy of the particles, the higher the temperature of the substance. The kinetic energy of a particle is determined by its mass and speed. For a pure substance, the greater the mass of each particle in the substance and the higher the average speed of the particles, the higher their average kinetic energy. The particles in both samples have the same average speed, but each particle in sample A has more mass than each particle in sample B. So, the particles in sample A have a higher average kinetic energy than the particles in sample B. Because the particles in sample A have the higher average kinetic energy, sample A must have the higher temperature.

sample A

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Is the following statement about our solar system true or false? 50% of the planets are made mainly of gas.

natural science

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice.

The table tells you that two out of the eight planets are made mainly of gas. So, one-fourth, or 25%, of the planets are made mainly of gas.

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The table tells you that two out of the eight planets are made mainly of gas. So, one-fourth, or 25%, of the planets are made mainly of gas.

false

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Select the amphibian below.

natural science

Birds, mammals, fish, reptiles, and amphibians are groups of animals. Scientists sort animals into each group based on traits they have in common. This process is called classification. Classification helps scientists learn about how animals live. Classification also helps scientists compare similar animals.

A Nile crocodile is a reptile. It has scaly, waterproof skin. Crocodiles hunt their prey in or near water. A giant moray is a fish. It lives underwater. It has fins, not limbs. Eels are long and thin. They may have small fins. They look like snakes, but they are fish! A red-headed poison frog is an amphibian. It has moist skin and begins its life in water. Poison dart frogs come in many bright colors. Their bright color warns other animals that these frogs are poisonous. A clownfish is a fish. It lives underwater. It has fins, not limbs. Clownfish live with animals called anemones. In the image of the clownfish, you can see the green anemone behind the clownfish.

Birds, mammals, fish, reptiles, and amphibians are groups of animals. Scientists sort animals into each group based on traits they have in common. This process is called classification. Classification helps scientists learn about how animals live. Classification also helps scientists compare similar animals. A Nile crocodile is a reptile. It has scaly, waterproof skin. Crocodiles hunt their prey in or near water. A giant moray is a fish. It lives underwater. It has fins, not limbs. Eels are long and thin. They may have small fins. They look like snakes, but they are fish! A red-headed poison frog is an amphibian. It has moist skin and begins its life in water. Poison dart frogs come in many bright colors. Their bright color warns other animals that these frogs are poisonous. A clownfish is a fish. It lives underwater. It has fins, not limbs. Clownfish live with animals called anemones. In the image of the clownfish, you can see the green anemone behind the clownfish.

red-headed poison frog

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Which property do these three objects have in common?

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification.

Look at each object. For each object, decide if it has that property. A hard object does not change shape when pressed or squeezed. The water pitcher and the marbles are hard, but the silk tie is not. Potato chips have a salty taste. The water pitcher is not salty. A smooth object is not scratchy or rough. All three objects are smooth. The property that all three objects have in common is smooth.

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification. Look at each object. For each object, decide if it has that property. A hard object does not change shape when pressed or squeezed. The water pitcher and the marbles are hard, but the silk tie is not. Potato chips have a salty taste. The water pitcher is not salty. A smooth object is not scratchy or rough. All three objects are smooth. The property that all three objects have in common is smooth.

smooth

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What is the expected ratio of offspring that do not have Huntington's disease to offspring that have Huntington's disease? Choose the most likely ratio.

natural science

Offspring phenotypes: dominant or recessive? How do you determine an organism's phenotype for a trait? Look at the combination of alleles in the organism's genotype for the gene that affects that trait. Some alleles have types called dominant and recessive. These two types can cause different versions of the trait to appear as the organism's phenotype. If an organism's genotype has at least one dominant allele for a gene, the organism's phenotype will be the dominant allele's version of the gene's trait. If an organism's genotype has only recessive alleles for a gene, the organism's phenotype will be the recessive allele's version of the gene's trait. A Punnett square shows what types of offspring a cross can produce. The expected ratio of offspring types compares how often the cross produces each type of offspring, on average. To write this ratio, count the number of boxes in the Punnett square representing each type. For example, consider the Punnett square below. | F | f F | FF | Ff f | Ff | ff There is 1 box with the genotype FF and 2 boxes with the genotype Ff. So, the expected ratio of offspring with the genotype FF to those with Ff is 1:2.

To determine how many boxes in the Punnett square represent offspring that do or do not have Huntington's disease, consider whether each phenotype is the dominant or recessive allele's version of the Huntington's disease trait. The question tells you that the h allele, which is for not having Huntington's disease, is recessive to the H allele, which is for having Huntington's disease. Not having Huntington's disease is the recessive allele's version of the Huntington's disease trait. A human with the recessive version of the Huntington's disease trait must have only recessive alleles for the Huntington's disease gene. So, offspring that do not have Huntington's disease must have the genotype hh. There are 2 boxes in the Punnett square with the genotype hh. These boxes are highlighted below. Having Huntington's disease is the dominant allele's version of the Huntington's disease trait. A human with the dominant version of the Huntington's disease trait must have at least one dominant allele for the Huntington's disease gene. So, offspring that have Huntington's disease must have the genotype HH or Hh. There are 2 boxes in the Punnett square with the genotype HH or Hh. These boxes are highlighted below. So, the expected ratio of offspring that do not have Huntington's disease to offspring that have Huntington's disease is 2:2. This means that, on average, this cross will produce 2 offspring that do not have Huntington's disease for every 2 offspring that have Huntington's disease.

Offspring phenotypes: dominant or recessive? How do you determine an organism's phenotype for a trait? Look at the combination of alleles in the organism's genotype for the gene that affects that trait. Some alleles have types called dominant and recessive. These two types can cause different versions of the trait to appear as the organism's phenotype. If an organism's genotype has at least one dominant allele for a gene, the organism's phenotype will be the dominant allele's version of the gene's trait. If an organism's genotype has only recessive alleles for a gene, the organism's phenotype will be the recessive allele's version of the gene's trait. A Punnett square shows what types of offspring a cross can produce. The expected ratio of offspring types compares how often the cross produces each type of offspring, on average. To write this ratio, count the number of boxes in the Punnett square representing each type. For example, consider the Punnett square below. | F | f F | FF | Ff f | Ff | ff There is 1 box with the genotype FF and 2 boxes with the genotype Ff. So, the expected ratio of offspring with the genotype FF to those with Ff is 1:2. To determine how many boxes in the Punnett square represent offspring that do or do not have Huntington's disease, consider whether each phenotype is the dominant or recessive allele's version of the Huntington's disease trait. The question tells you that the h allele, which is for not having Huntington's disease, is recessive to the H allele, which is for having Huntington's disease. Not having Huntington's disease is the recessive allele's version of the Huntington's disease trait. A human with the recessive version of the Huntington's disease trait must have only recessive alleles for the Huntington's disease gene. So, offspring that do not have Huntington's disease must have the genotype hh. There are 2 boxes in the Punnett square with the genotype hh. These boxes are highlighted below. Having Huntington's disease is the dominant allele's version of the Huntington's disease trait. A human with the dominant version of the Huntington's disease trait must have at least one dominant allele for the Huntington's disease gene. So, offspring that have Huntington's disease must have the genotype HH or Hh. There are 2 boxes in the Punnett square with the genotype HH or Hh. These boxes are highlighted below. So, the expected ratio of offspring that do not have Huntington's disease to offspring that have Huntington's disease is 2:2. This means that, on average, this cross will produce 2 offspring that do not have Huntington's disease for every 2 offspring that have Huntington's disease.

2:2

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Based on the arrows, which of the following organisms is a producer?

natural science

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web.

Producers do not eat other organisms. So, in a food web, producers do not have arrows pointing to them from other organisms. The barren-ground caribou has an arrow pointing to it from the lichen. So, the barren-ground caribou is a consumer, not a producer. The bilberry does not have any arrows pointing to it. So, the bilberry is a producer.

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web. Producers do not eat other organisms. So, in a food web, producers do not have arrows pointing to them from other organisms. The barren-ground caribou has an arrow pointing to it from the lichen. So, the barren-ground caribou is a consumer, not a producer. The bilberry does not have any arrows pointing to it. So, the bilberry is a producer.

bilberry

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Which property do these three objects have in common?

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification.

Look at each object. For each object, decide if it has that property. Blue is a color. This color is blue. None of the objects are blue. A hard object does not change shape when pressed or squeezed. The potato sack and the velcro are not hard. A scratchy object is rough and itchy against your skin. All three objects are scratchy. The property that all three objects have in common is scratchy.

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification. Look at each object. For each object, decide if it has that property. Blue is a color. This color is blue. None of the objects are blue. A hard object does not change shape when pressed or squeezed. The potato sack and the velcro are not hard. A scratchy object is rough and itchy against your skin. All three objects are scratchy. The property that all three objects have in common is scratchy.

scratchy

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During this time, thermal energy was transferred from () to ().

natural science

A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings.

The temperature of each cake decreased, which means that the thermal energy of each cake decreased. So, thermal energy was transferred from each cake to the surroundings.

A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings. The temperature of each cake decreased, which means that the thermal energy of each cake decreased. So, thermal energy was transferred from each cake to the surroundings.

each cake . . . the surroundings

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Which of these organisms contains matter that was once part of the bilberry?

natural science

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web.

Use the arrows to follow how matter moves through this food web. For each answer choice, try to find a path of arrows that starts from the bilberry. The bear sedge does not have any arrows pointing to it. So, in this food web, matter does not move from the bilberry to the bear sedge. The only arrow pointing to the barren-ground caribou starts from the lichen. The lichen does not have any arrows pointing to it. So, in this food web, matter does not move from the bilberry to the barren-ground caribou. The lichen does not have any arrows pointing to it. So, in this food web, matter does not move from the bilberry to the lichen.There are four paths matter can take from the bilberry to the earthworm: bilberry->Arctic fox->earthworm. bilberry->brown lemming->Arctic fox->earthworm. bilberry->brown lemming->snowy owl->earthworm. bilberry->brown lemming->parasitic jaeger->rough-legged hawk->earthworm. There is one path matter can take from the bilberry to the rough-legged hawk: bilberry->brown lemming->parasitic jaeger->rough-legged hawk.

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web. Use the arrows to follow how matter moves through this food web. For each answer choice, try to find a path of arrows that starts from the bilberry. The bear sedge does not have any arrows pointing to it. So, in this food web, matter does not move from the bilberry to the bear sedge. The only arrow pointing to the barren-ground caribou starts from the lichen. The lichen does not have any arrows pointing to it. So, in this food web, matter does not move from the bilberry to the barren-ground caribou. The lichen does not have any arrows pointing to it. So, in this food web, matter does not move from the bilberry to the lichen.There are four paths matter can take from the bilberry to the earthworm: bilberry->Arctic fox->earthworm. bilberry->brown lemming->Arctic fox->earthworm. bilberry->brown lemming->snowy owl->earthworm. bilberry->brown lemming->parasitic jaeger->rough-legged hawk->earthworm. There is one path matter can take from the bilberry to the rough-legged hawk: bilberry->brown lemming->parasitic jaeger->rough-legged hawk.

rough-legged hawk

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other.

Distance affects the strength of the magnetic force. But the distance between the magnets in Pair 1 and in Pair 2 is the same. So, the strength of the magnetic force is the same in both pairs.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. Distance affects the strength of the magnetic force. But the distance between the magnets in Pair 1 and in Pair 2 is the same. So, the strength of the magnetic force is the same in both pairs.

The strength of the magnetic force is the same in both pairs.

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Which property matches this object?

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells.

Look at the object. Think about each property. Potato chips have a salty taste. The lemon is not salty. Yellow is a color. This color is yellow. The lemon is yellow.

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Look at the object. Think about each property. Potato chips have a salty taste. The lemon is not salty. Yellow is a color. This color is yellow. The lemon is yellow.

yellow

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Is a pipe cleaner a solid, a liquid, or a gas?

natural science

Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own. Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid. When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle. Some liquids do not pour as easily as others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk. When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space. Many gases are invisible. Air is a gas.

A pipe cleaner is a solid. You can easily bend a pipe cleaner. But it will still have a size and shape of its own.

Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own. Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid. When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle. Some liquids do not pour as easily as others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk. When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space. Many gases are invisible. Air is a gas. A pipe cleaner is a solid. You can easily bend a pipe cleaner. But it will still have a size and shape of its own.

a solid

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Is the following statement about our solar system true or false? The volume of Neptune is less than 75% of the volume of Uranus.

natural science

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice.

To determine if this statement is true, calculate the value of 75% of the volume of Uranus by multiplying its volume by 0.75. Then compare the result to the volume of Neptune. The volume of Neptune is 62,530 billion km^3, which is more than 51,248 billion km^3. So, the volume of Neptune is more than 75% of the volume of Uranus.

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. To determine if this statement is true, calculate the value of 75% of the volume of Uranus by multiplying its volume by 0.75. Then compare the result to the volume of Neptune. The volume of Neptune is 62,530 billion km^3, which is more than 51,248 billion km^3. So, the volume of Neptune is more than 75% of the volume of Uranus.

false

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Which three months have an average precipitation of around 3.5inches in Seattle?

natural science

Scientists record climate data from places around the world. Precipitation, or rain and snow, is one type of climate data. A bar graph can be used to show the average amount of precipitation each month. Months with taller bars have more precipitation on average.

To describe the average precipitation trends in Seattle, look at the graph. Choice "Feb" is incorrect. Choice "Mar" is incorrect. Choice "Apr" is incorrect. Choice "May" is incorrect. Choice "Jun" is incorrect. Choice "Jul" is incorrect. Choice "Oct" is incorrect. Choice "Nov" is incorrect. Choice "Dec" is incorrect. Choice "February, March, and October" is incorrect. February, March, and October each have an average precipitation of around 3.5 inches. Choice "April, May, and November" is incorrect. The average precipitation in April and May is less than 3 inches. And, the average precipitation in November is more than 6 inches. Choice "June, July, and December" is incorrect. The average precipitation in June and July is less than 2 inches. And, the average precipitation in December is more than 5 inches.

Scientists record climate data from places around the world. Precipitation, or rain and snow, is one type of climate data. A bar graph can be used to show the average amount of precipitation each month. Months with taller bars have more precipitation on average. To describe the average precipitation trends in Seattle, look at the graph. Choice "Feb" is incorrect. Choice "Mar" is incorrect. Choice "Apr" is incorrect. Choice "May" is incorrect. Choice "Jun" is incorrect. Choice "Jul" is incorrect. Choice "Oct" is incorrect. Choice "Nov" is incorrect. Choice "Dec" is incorrect. Choice "February, March, and October" is incorrect. February, March, and October each have an average precipitation of around 3.5 inches. Choice "April, May, and November" is incorrect. The average precipitation in April and May is less than 3 inches. And, the average precipitation in November is more than 6 inches. Choice "June, July, and December" is incorrect. The average precipitation in June and July is less than 2 inches. And, the average precipitation in December is more than 5 inches.

February, March, and October

e53c1b3de43845599609e06cfc70351b

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Which better describes the Monongahela National Forest ecosystem?

natural science

An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there

A temperate deciduous forest is a type of ecosystem. Temperate deciduous forests have the following features: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. So, the Monongahela National Forest has soil that is rich in nutrients. It also has only a few types of trees.

An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there A temperate deciduous forest is a type of ecosystem. Temperate deciduous forests have the following features: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. So, the Monongahela National Forest has soil that is rich in nutrients. It also has only a few types of trees.

It has soil that is rich in nutrients. It also has only a few types of trees.

767ced362b96450eab53e11c7cbc1fc2

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Which property do these four objects have in common?

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification.

Look at each object. For each object, decide if it has that property. An opaque object does not let light through. All four objects are opaque. A hard object does not change shape when pressed or squeezed. The road, the water slide, and the crayons are hard, but the track suit is not. A flexible object can be folded or bent without breaking easily. The track suit is flexible, but the road and the crayons are not. The property that all four objects have in common is opaque.

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification. Look at each object. For each object, decide if it has that property. An opaque object does not let light through. All four objects are opaque. A hard object does not change shape when pressed or squeezed. The road, the water slide, and the crayons are hard, but the track suit is not. A flexible object can be folded or bent without breaking easily. The track suit is flexible, but the road and the crayons are not. The property that all four objects have in common is opaque.

opaque

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The north pole of each magnet is labeled N, and the south pole is labeled S. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

To predict if these magnets will attract or repel, look at which poles are closest to each other. The south pole of one magnet is closest to the south pole of the other magnet. Like poles repel. So, these magnets will repel each other.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The north pole of each magnet is labeled N, and the south pole is labeled S. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. To predict if these magnets will attract or repel, look at which poles are closest to each other. The south pole of one magnet is closest to the south pole of the other magnet. Like poles repel. So, these magnets will repel each other.

repel

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the magnitude of a magnetic force between two magnets by using magnets of different sizes. The magnitude of the magnetic force is smaller when the magnets are smaller.

Magnet sizes affect the magnitude of the magnetic force. Imagine magnets that are the same shape and made of the same material. The smaller the magnets, the smaller the magnitude of the magnetic force between them. Magnet A is the same size in both pairs. But Magnet B is smaller in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is smaller in Pair 2 than in Pair 1.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the magnitude of a magnetic force between two magnets by using magnets of different sizes. The magnitude of the magnetic force is smaller when the magnets are smaller. Magnet sizes affect the magnitude of the magnetic force. Imagine magnets that are the same shape and made of the same material. The smaller the magnets, the smaller the magnitude of the magnetic force between them. Magnet A is the same size in both pairs. But Magnet B is smaller in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is smaller in Pair 2 than in Pair 1.

The magnitude of the magnetic force is smaller in Pair 2.

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Is biotite a mineral?

natural science

Properties are used to identify different substances. Minerals have the following properties: It is a solid. It is formed in nature. It is not made by organisms. It is a pure substance. It has a fixed crystal structure. If a substance has all five of these properties, then it is a mineral. Look closely at the last three properties: A mineral is not made by organisms. Organisms make their own body parts. For example, snails and clams make their shells. Because they are made by organisms, body parts cannot be minerals. Humans are organisms too. So, substances that humans make by hand or in factories cannot be minerals. A mineral is a pure substance. A pure substance is made of only one type of matter. All minerals are pure substances. A mineral has a fixed crystal structure. The crystal structure of a substance tells you how the atoms or molecules in the substance are arranged. Different types of minerals have different crystal structures, but all minerals have a fixed crystal structure. This means that the atoms or molecules in different pieces of the same type of mineral are always arranged the same way.

Biotite has all the properties of a mineral. So, biotite is a mineral.

Properties are used to identify different substances. Minerals have the following properties: It is a solid. It is formed in nature. It is not made by organisms. It is a pure substance. It has a fixed crystal structure. If a substance has all five of these properties, then it is a mineral. Look closely at the last three properties: A mineral is not made by organisms. Organisms make their own body parts. For example, snails and clams make their shells. Because they are made by organisms, body parts cannot be minerals. Humans are organisms too. So, substances that humans make by hand or in factories cannot be minerals. A mineral is a pure substance. A pure substance is made of only one type of matter. All minerals are pure substances. A mineral has a fixed crystal structure. The crystal structure of a substance tells you how the atoms or molecules in the substance are arranged. Different types of minerals have different crystal structures, but all minerals have a fixed crystal structure. This means that the atoms or molecules in different pieces of the same type of mineral are always arranged the same way. Biotite has all the properties of a mineral. So, biotite is a mineral.

yes

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other.

Both magnet sizes and distance affect the magnitude of the magnetic force. The sizes of the magnets in Pair 1 are the same as in Pair 2. The distance between the magnets is also the same. So, the magnitude of the magnetic force is the same in both pairs.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. Both magnet sizes and distance affect the magnitude of the magnetic force. The sizes of the magnets in Pair 1 are the same as in Pair 2. The distance between the magnets is also the same. So, the magnitude of the magnetic force is the same in both pairs.

The magnitude of the magnetic force is the same in both pairs.

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Which of the following fossils is younger? Select the more likely answer.

natural science

A fossil is the preserved evidence of an ancient organism. Some fossils are formed from body parts such as bones or shells. Other fossils, such as footprints or burrows, are formed from traces of an organism's activities. Fossils are typically found in sedimentary rocks. Sedimentary rocks usually form in layers. Over time, new layers are added on top of old layers in a series called a rock sequence. The layers in an undisturbed rock sequence are in the same order as when they formed. So, the deeper layers are older than the shallower layers. The relative ages of fossils can be determined from their positions in an undisturbed rock sequence. Older fossils are usually in deeper layers, and younger fossils are usually in shallower layers.

Look again at the fossils in the rock sequence diagram. Compare the positions of these fossils to determine which one is younger: The insect fossil is in a shallower layer in the rock sequence than the dinosaur footprint fossil. So, the insect fossil is most likely younger than the dinosaur footprint fossil.

A fossil is the preserved evidence of an ancient organism. Some fossils are formed from body parts such as bones or shells. Other fossils, such as footprints or burrows, are formed from traces of an organism's activities. Fossils are typically found in sedimentary rocks. Sedimentary rocks usually form in layers. Over time, new layers are added on top of old layers in a series called a rock sequence. The layers in an undisturbed rock sequence are in the same order as when they formed. So, the deeper layers are older than the shallower layers. The relative ages of fossils can be determined from their positions in an undisturbed rock sequence. Older fossils are usually in deeper layers, and younger fossils are usually in shallower layers. Look again at the fossils in the rock sequence diagram. Compare the positions of these fossils to determine which one is younger: The insect fossil is in a shallower layer in the rock sequence than the dinosaur footprint fossil. So, the insect fossil is most likely younger than the dinosaur footprint fossil.

insect

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In this experiment, which were part of an experimental group?

natural science

Experiments have variables, or parts that change. You can design an experiment to investigate whether changing a variable between different groups has a specific outcome. For example, imagine you want to find out whether adding fertilizer to soil affects the height of pea plants. You could investigate this question with the following experiment: You grow one group of pea plants in soil with fertilizer and measure the height of the plants. This group shows you what happens when fertilizer is added to soil. Since fertilizer is the variable whose effect you are investigating, this group is an experimental group. You grow another group of pea plants in soil without fertilizer and measure the height of the plants. Since this group shows you what happens when fertilizer is not added to the soil, it is a control group. By comparing the results from the experimental group to the results from the control group, you can conclude whether adding fertilizer to the soil affects pea plant height.

In this experiment, Steve investigated whether removing carbon dioxide from soda affects how quickly the soda freezes. So, the bottles with lids taken off were part of an experimental group. Carbon dioxide was not removed from the bottles with lids kept on. So, they were not part of an experimental group.

Experiments have variables, or parts that change. You can design an experiment to investigate whether changing a variable between different groups has a specific outcome. For example, imagine you want to find out whether adding fertilizer to soil affects the height of pea plants. You could investigate this question with the following experiment: You grow one group of pea plants in soil with fertilizer and measure the height of the plants. This group shows you what happens when fertilizer is added to soil. Since fertilizer is the variable whose effect you are investigating, this group is an experimental group. You grow another group of pea plants in soil without fertilizer and measure the height of the plants. Since this group shows you what happens when fertilizer is not added to the soil, it is a control group. By comparing the results from the experimental group to the results from the control group, you can conclude whether adding fertilizer to the soil affects pea plant height. In this experiment, Steve investigated whether removing carbon dioxide from soda affects how quickly the soda freezes. So, the bottles with lids taken off were part of an experimental group. Carbon dioxide was not removed from the bottles with lids kept on. So, they were not part of an experimental group.

the bottles with lids taken off

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Which of these organisms contains matter that was once part of the bear sedge?

natural science

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web.

Use the arrows to follow how matter moves through this food web. For each answer choice, try to find a path of arrows that starts from the bear sedge.There is one path matter can take from the bear sedge to the rough-legged hawk: bear sedge->brown lemming->parasitic jaeger->rough-legged hawk. There is one path matter can take from the bear sedge to the Arctic fox: bear sedge->brown lemming->Arctic fox. mushroom. The mushroom has two arrows pointing to it. One arrow starts from the barren-ground caribou. The only arrow pointing to the barren-ground caribou starts from the lichen. The lichen does not have any arrows pointing to it. The other arrow pointing to the mushroom starts from the grizzly bear. The grizzly bear has two arrows pointing to it. One arrow starts from the bilberry. The bilberry does not have any arrows pointing to it. The other arrow pointing to the grizzly bear starts from the barren-ground caribou. The only arrow pointing to the barren-ground caribou starts from the lichen. The lichen does not have any arrows pointing to it. So, in this food web, matter does not move from the bear sedge to the mushroom.. There is one path matter can take from the bear sedge to the snowy owl: bear sedge->brown lemming->short-tailed weasel->snowy owl. There is one path matter can take from the bear sedge to the short-tailed weasel: bear sedge->brown lemming->short-tailed weasel.

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web. Use the arrows to follow how matter moves through this food web. For each answer choice, try to find a path of arrows that starts from the bear sedge.There is one path matter can take from the bear sedge to the rough-legged hawk: bear sedge->brown lemming->parasitic jaeger->rough-legged hawk. There is one path matter can take from the bear sedge to the Arctic fox: bear sedge->brown lemming->Arctic fox. mushroom. The mushroom has two arrows pointing to it. One arrow starts from the barren-ground caribou. The only arrow pointing to the barren-ground caribou starts from the lichen. The lichen does not have any arrows pointing to it. The other arrow pointing to the mushroom starts from the grizzly bear. The grizzly bear has two arrows pointing to it. One arrow starts from the bilberry. The bilberry does not have any arrows pointing to it. The other arrow pointing to the grizzly bear starts from the barren-ground caribou. The only arrow pointing to the barren-ground caribou starts from the lichen. The lichen does not have any arrows pointing to it. So, in this food web, matter does not move from the bear sedge to the mushroom.. There is one path matter can take from the bear sedge to the snowy owl: bear sedge->brown lemming->short-tailed weasel->snowy owl. There is one path matter can take from the bear sedge to the short-tailed weasel: bear sedge->brown lemming->short-tailed weasel.

snowy owl

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is stronger when the magnets are closer together.

Distance affects the strength of the magnetic force. When magnets are closer together, the magnetic force between them is stronger. The magnets in Pair 1 are closer together than the magnets in Pair 2. So, the magnetic force is stronger in Pair 1 than in Pair 2.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is stronger when the magnets are closer together. Distance affects the strength of the magnetic force. When magnets are closer together, the magnetic force between them is stronger. The magnets in Pair 1 are closer together than the magnets in Pair 2. So, the magnetic force is stronger in Pair 1 than in Pair 2.

The magnetic force is stronger in Pair 1.

956840bf151b4faea3392104316bc9c0

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Which solution has a higher concentration of purple particles?

natural science

A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent. The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent. concentration = particles of solute / volume of solvent

In Solution A and Solution B, the purple particles represent the solute. To figure out which solution has a higher concentration of purple particles, look at both the number of purple particles and the volume of the solvent in each container. Use the concentration formula to find the number of purple particles per milliliter. Solution A has more purple particles per milliliter. So, Solution A has a higher concentration of purple particles.

A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent. The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent. concentration = particles of solute / volume of solvent In Solution A and Solution B, the purple particles represent the solute. To figure out which solution has a higher concentration of purple particles, look at both the number of purple particles and the volume of the solvent in each container. Use the concentration formula to find the number of purple particles per milliliter. Solution A has more purple particles per milliliter. So, Solution A has a higher concentration of purple particles.

Solution A

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During this time, thermal energy was transferred from () to ().

natural science

A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings.

The temperature of each aquarium decreased, which means that the thermal energy of each aquarium decreased. So, thermal energy was transferred from each aquarium to the surroundings.

A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings. The temperature of each aquarium decreased, which means that the thermal energy of each aquarium decreased. So, thermal energy was transferred from each aquarium to the surroundings.

each aquarium . . . the surroundings

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Which animal is also adapted to use its neck to appear large and scary to a predator?

natural science

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The shape of an animal's neck is one example of an adaptation. Animals' necks can be adapted in different ways. For example, a large frilled neck might help an animal appear dangerous to its predators. A long neck might help an animal get food from tall trees.

Look at the picture of the Mozambique spitting cobra. When frightened, the Mozambique spitting cobra can spread out its hood to appear larger and more dangerous. If a predator is nearby, the hood can help scare it away. Now look at each animal. Figure out which animal has a similar adaptation. The bearded dragon has spiny scales around its neck. It uses its neck to appear larger and more dangerous to a predator. The lace monitor has a narrow neck. Its neck is not adapted to help it appear larger and more dangerous to a predator.

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The shape of an animal's neck is one example of an adaptation. Animals' necks can be adapted in different ways. For example, a large frilled neck might help an animal appear dangerous to its predators. A long neck might help an animal get food from tall trees. Look at the picture of the Mozambique spitting cobra. When frightened, the Mozambique spitting cobra can spread out its hood to appear larger and more dangerous. If a predator is nearby, the hood can help scare it away. Now look at each animal. Figure out which animal has a similar adaptation. The bearded dragon has spiny scales around its neck. It uses its neck to appear larger and more dangerous to a predator. The lace monitor has a narrow neck. Its neck is not adapted to help it appear larger and more dangerous to a predator.

bearded dragon

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Which of these organisms contains matter that was once part of the lichen?

natural science

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web.

Use the arrows to follow how matter moves through this food web. For each answer choice, try to find a path of arrows that starts from the lichen. No arrow points to the bilberry. So, in this food web, matter does not move from the lichen to the bilberry.

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web. Use the arrows to follow how matter moves through this food web. For each answer choice, try to find a path of arrows that starts from the lichen. No arrow points to the bilberry. So, in this food web, matter does not move from the lichen to the bilberry.

collared lemming

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Which continent is highlighted?

social science

A continent is one of the seven largest areas of land on earth.

This continent is Antarctica.

A continent is one of the seven largest areas of land on earth. This continent is Antarctica.

Antarctica

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is stronger when the magnets are closer together.

Distance affects the strength of the magnetic force. When magnets are closer together, the magnetic force between them is stronger. The magnets in Pair 2 are closer together than the magnets in Pair 1. So, the magnetic force is stronger in Pair 2 than in Pair 1.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is stronger when the magnets are closer together. Distance affects the strength of the magnetic force. When magnets are closer together, the magnetic force between them is stronger. The magnets in Pair 2 are closer together than the magnets in Pair 1. So, the magnetic force is stronger in Pair 2 than in Pair 1.

The magnetic force is stronger in Pair 2.

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Based on the arrows, which of the following organisms is an omnivore?

natural science

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web.

Omnivores are consumers that eat both producers and other consumers. So, an omnivore has arrows pointing to it from at least one producer and at least one consumer. The bilberry does not have any arrows pointing to it. So, the bilberry is a producer, not an omnivore. The Arctic fox has an arrow pointing to it from the bilberry, which is a producer. The Arctic fox also has an arrow pointing to it from the collared lemming, which is a consumer. The Arctic fox eats a producer and a consumer, so it is an omnivore.

A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web. Omnivores are consumers that eat both producers and other consumers. So, an omnivore has arrows pointing to it from at least one producer and at least one consumer. The bilberry does not have any arrows pointing to it. So, the bilberry is a producer, not an omnivore. The Arctic fox has an arrow pointing to it from the bilberry, which is a producer. The Arctic fox also has an arrow pointing to it from the collared lemming, which is a consumer. The Arctic fox eats a producer and a consumer, so it is an omnivore.

Arctic fox

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Is rainbow quartz a solid, a liquid, or a gas?

natural science

Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own. Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid. When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle. Some liquids are thicker than others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk. When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space. Many gases are invisible. The oxygen you breathe is a gas. The helium in a balloon is also a gas.

Rainbow quartz is a type of rock. A rock is a solid with a size and shape of its own.

Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own. Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid. When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle. Some liquids are thicker than others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk. When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space. Many gases are invisible. The oxygen you breathe is a gas. The helium in a balloon is also a gas. Rainbow quartz is a type of rock. A rock is a solid with a size and shape of its own.

a solid

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During this time, thermal energy was transferred from () to ().

natural science

A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings.

The temperature of each aquarium decreased, which means that the thermal energy of each aquarium decreased. So, thermal energy was transferred from each aquarium to the surroundings.

A change in an object's temperature indicates a change in the object's thermal energy: An increase in temperature shows that the object's thermal energy increased. So, thermal energy was transferred into the object from its surroundings. A decrease in temperature shows that the object's thermal energy decreased. So, thermal energy was transferred out of the object to its surroundings. The temperature of each aquarium decreased, which means that the thermal energy of each aquarium decreased. So, thermal energy was transferred from each aquarium to the surroundings.

each aquarium . . . the surroundings

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the magnitude of a magnetic force between two magnets by using magnets of different sizes. The magnitude of the magnetic force is smaller when the magnets are smaller.

The magnets in Pair 1 attract. The magnets in Pair 2 repel. But whether the magnets attract or repel affects only the direction of the magnetic force. It does not affect the magnitude of the magnetic force. Magnet sizes affect the magnitude of the magnetic force. Imagine magnets that are the same shape and made of the same material. The smaller the magnets, the smaller the magnitude of the magnetic force between them. Magnet A is the same size in both pairs. But Magnet B is smaller in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is smaller in Pair 2 than in Pair 1.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the magnitude of a magnetic force between two magnets by using magnets of different sizes. The magnitude of the magnetic force is smaller when the magnets are smaller. The magnets in Pair 1 attract. The magnets in Pair 2 repel. But whether the magnets attract or repel affects only the direction of the magnetic force. It does not affect the magnitude of the magnetic force. Magnet sizes affect the magnitude of the magnetic force. Imagine magnets that are the same shape and made of the same material. The smaller the magnets, the smaller the magnitude of the magnetic force between them. Magnet A is the same size in both pairs. But Magnet B is smaller in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is smaller in Pair 2 than in Pair 1.

The magnitude of the magnetic force is smaller in Pair 2.

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Which is this organism's scientific name?

natural science

An organism's common name is the name that people normally call the organism. Common names often contain words you know. An organism's scientific name is the name scientists use to identify the organism. Scientific names often contain words that are not used in everyday English. Scientific names are written in italics, but common names are usually not. The first word of the scientific name is capitalized, and the second word is not. For example, the common name of the animal below is giant panda. Its scientific name is Ailuropoda melanoleuca.

Cyprinus carpio is written in italics. The first word is capitalized, and the second word is not. So, Cyprinus carpio is the scientific name.

An organism's common name is the name that people normally call the organism. Common names often contain words you know. An organism's scientific name is the name scientists use to identify the organism. Scientific names often contain words that are not used in everyday English. Scientific names are written in italics, but common names are usually not. The first word of the scientific name is capitalized, and the second word is not. For example, the common name of the animal below is giant panda. Its scientific name is Ailuropoda melanoleuca. Cyprinus carpio is written in italics. The first word is capitalized, and the second word is not. So, Cyprinus carpio is the scientific name.

Cyprinus carpio

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Is oxygen a solid, a liquid, or a gas?

natural science

Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own. Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid. When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle. Some liquids do not pour as easily as others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk. When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space. Many gases are invisible. Air is a gas.

Oxygen is a gas. A gas expands to fill a space. Oxygen can be stored in metal tanks. If oxygen leaks out of the tank, the oxygen will expand into the space around the tank.

Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own. Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid. When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle. Some liquids do not pour as easily as others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk. When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space. Many gases are invisible. Air is a gas. Oxygen is a gas. A gas expands to fill a space. Oxygen can be stored in metal tanks. If oxygen leaks out of the tank, the oxygen will expand into the space around the tank.

a gas

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other.

Both magnet sizes and distance affect the magnitude of the magnetic force. The sizes of the magnets in Pair 1 are the same as in Pair 2. The distance between the magnets is also the same. So, the magnitude of the magnetic force is the same in both pairs.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. Both magnet sizes and distance affect the magnitude of the magnetic force. The sizes of the magnets in Pair 1 are the same as in Pair 2. The distance between the magnets is also the same. So, the magnitude of the magnetic force is the same in both pairs.

The magnitude of the magnetic force is the same in both pairs.

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Is the following statement about our solar system true or false? Jupiter's volume is more than 1,000 times that of Earth.

natural science

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For example, the volume of Jupiter is 1,430,000,000,000,000 km^3. In scientific notation, Jupiter's volume is written as 1.43 x 10^15 km^3. To compare two numbers written in scientific notation, first compare their exponents. The bigger the exponent is, the bigger the number is. For example: 1.43 x 10^15 is larger than 1.43 x 10^12 If their exponents are equal, compare the first numbers. For example: 1.43 x 10^15 is larger than 1.25 x 10^15 To multiply a number written in scientific notation by a power of 10, write the multiple of 10 as 10 raised to an exponent. Then, add the exponents. For example: 1.43 x 10^15 · 1000 = 1.43 x 10^15 · 10^3 = 1.43 x 10^(15 + 3) = 1.43 x 10^18

To determine if this statement is true, calculate the value of 1,000 times the volume of Earth. Then compare the result to the volume of Jupiter. The volume of Jupiter is 1.43 x 10^15 km^3, which is more than 1.08 x 10^15 km^3. So, Jupiter's volume is more than 1,000 times that of Earth.

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For example, the volume of Jupiter is 1,430,000,000,000,000 km^3. In scientific notation, Jupiter's volume is written as 1.43 x 10^15 km^3. To compare two numbers written in scientific notation, first compare their exponents. The bigger the exponent is, the bigger the number is. For example: 1.43 x 10^15 is larger than 1.43 x 10^12 If their exponents are equal, compare the first numbers. For example: 1.43 x 10^15 is larger than 1.25 x 10^15 To multiply a number written in scientific notation by a power of 10, write the multiple of 10 as 10 raised to an exponent. Then, add the exponents. For example: 1.43 x 10^15 · 1000 = 1.43 x 10^15 · 10^3 = 1.43 x 10^(15 + 3) = 1.43 x 10^18 To determine if this statement is true, calculate the value of 1,000 times the volume of Earth. Then compare the result to the volume of Jupiter. The volume of Jupiter is 1.43 x 10^15 km^3, which is more than 1.08 x 10^15 km^3. So, Jupiter's volume is more than 1,000 times that of Earth.

true

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S). Here are some examples of magnets. Their poles are shown in different colors and labeled. Whether a magnet attracts or repels other magnets depends on the positions of its poles. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

To predict if these magnets will attract or repel, look at which poles are closest to each other. The south pole of one magnet is closest to the north pole of the other magnet. Opposite poles attract. So, these magnets will attract each other.

Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S). Here are some examples of magnets. Their poles are shown in different colors and labeled. Whether a magnet attracts or repels other magnets depends on the positions of its poles. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. To predict if these magnets will attract or repel, look at which poles are closest to each other. The south pole of one magnet is closest to the north pole of the other magnet. Opposite poles attract. So, these magnets will attract each other.

attract

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Which of the following fossils is younger? Select the more likely answer.

natural science

A fossil is the preserved evidence of an ancient organism. Some fossils are formed from body parts such as bones or shells. Other fossils, such as footprints or burrows, are formed from traces of an organism's activities. Fossils are typically found in sedimentary rocks. Sedimentary rocks usually form in layers. Over time, new layers are added on top of old layers in a series called a rock sequence. The layers in an undisturbed rock sequence are in the same order as when they formed. So, the deeper layers are older than the shallower layers. The relative ages of fossils can be determined from their positions in an undisturbed rock sequence. Older fossils are usually in deeper layers, and younger fossils are usually in shallower layers.

Look again at the fossils in the rock sequence diagram. Compare the positions of these fossils to determine which one is younger: The fern fossil is in a shallower layer in the rock sequence than the feather fossil. So, the fern fossil is most likely younger than the feather fossil.

A fossil is the preserved evidence of an ancient organism. Some fossils are formed from body parts such as bones or shells. Other fossils, such as footprints or burrows, are formed from traces of an organism's activities. Fossils are typically found in sedimentary rocks. Sedimentary rocks usually form in layers. Over time, new layers are added on top of old layers in a series called a rock sequence. The layers in an undisturbed rock sequence are in the same order as when they formed. So, the deeper layers are older than the shallower layers. The relative ages of fossils can be determined from their positions in an undisturbed rock sequence. Older fossils are usually in deeper layers, and younger fossils are usually in shallower layers. Look again at the fossils in the rock sequence diagram. Compare the positions of these fossils to determine which one is younger: The fern fossil is in a shallower layer in the rock sequence than the feather fossil. So, the fern fossil is most likely younger than the feather fossil.

fern

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Which two months have the lowest average precipitation in Salt Lake City?

natural science

Scientists record climate data from places around the world. Precipitation, or rain and snow, is one type of climate data. Scientists collect data over many years. They can use this data to calculate the average precipitation for each month. The average precipitation can be used to describe the climate of a location. A bar graph can be used to show the average amount of precipitation each month. Months with taller bars have more precipitation on average.

To describe the average precipitation trends in Salt Lake City, look at the graph. Choice "Feb" is incorrect. Choice "Mar" is incorrect. Choice "Jul" is incorrect. Choice "Aug" is incorrect. Choice "Nov" is incorrect. Choice "Dec" is incorrect. July and August each have an average precipitation of less than 1 inch. All other months have a higher average precipitation.

Scientists record climate data from places around the world. Precipitation, or rain and snow, is one type of climate data. Scientists collect data over many years. They can use this data to calculate the average precipitation for each month. The average precipitation can be used to describe the climate of a location. A bar graph can be used to show the average amount of precipitation each month. Months with taller bars have more precipitation on average. To describe the average precipitation trends in Salt Lake City, look at the graph. Choice "Feb" is incorrect. Choice "Mar" is incorrect. Choice "Jul" is incorrect. Choice "Aug" is incorrect. Choice "Nov" is incorrect. Choice "Dec" is incorrect. July and August each have an average precipitation of less than 1 inch. All other months have a higher average precipitation.

July and August

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Select the mammal below.

natural science

Birds, mammals, fish, reptiles, and amphibians are groups of animals. The animals in each group have traits in common. Scientists sort animals into groups based on traits they have in common. This process is called classification.

A sea otter is a mammal. It has fur and feeds its young milk. A salmon is a fish. It lives underwater. It has fins, not limbs.

Birds, mammals, fish, reptiles, and amphibians are groups of animals. The animals in each group have traits in common. Scientists sort animals into groups based on traits they have in common. This process is called classification. A sea otter is a mammal. It has fur and feeds its young milk. A salmon is a fish. It lives underwater. It has fins, not limbs.

sea otter

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles, called north and south. Here are some examples of magnets. The north pole of each magnet is marked N, and the south pole is marked S. If different poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

Will these magnets attract or repel? To find out, look at which poles are closest to each other. The south pole of one magnet is closest to the south pole of the other magnet. Poles that are the same repel. So, these magnets will repel each other.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles, called north and south. Here are some examples of magnets. The north pole of each magnet is marked N, and the south pole is marked S. If different poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same poles are closest to each other, the magnets repel. The magnets in both pairs below repel. Will these magnets attract or repel? To find out, look at which poles are closest to each other. The south pole of one magnet is closest to the south pole of the other magnet. Poles that are the same repel. So, these magnets will repel each other.

repel

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles, called north and south. Here are some examples of magnets. The north pole of each magnet is marked N, and the south pole is marked S. If different poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

Will these magnets attract or repel? To find out, look at which poles are closest to each other. The south pole of one magnet is closest to the north pole of the other magnet. Poles that are different attract. So, these magnets will attract each other.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles, called north and south. Here are some examples of magnets. The north pole of each magnet is marked N, and the south pole is marked S. If different poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same poles are closest to each other, the magnets repel. The magnets in both pairs below repel. Will these magnets attract or repel? To find out, look at which poles are closest to each other. The south pole of one magnet is closest to the north pole of the other magnet. Poles that are different attract. So, these magnets will attract each other.

attract

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What is the direction of this push?

natural science

One object can make another object move with a push or a pull. The direction of a push is away from the object that is pushing. The direction of a pull is toward the object that is pulling.

A racket hitting a tennis ball is a type of push. The tennis player hits the ball away from his racket. So, the ball flies over the net. The direction of the push is away from the tennis racket.

One object can make another object move with a push or a pull. The direction of a push is away from the object that is pushing. The direction of a pull is toward the object that is pulling. A racket hitting a tennis ball is a type of push. The tennis player hits the ball away from his racket. So, the ball flies over the net. The direction of the push is away from the tennis racket.

away from the tennis racket

b72ed4d3920d47d09af7484ae7042883

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Complete the sentence. The Japan Trench formed at a () boundary.

natural science

The outer layer of Earth is broken up into many pieces called tectonic plates, or simply plates. The breaks between plates are called plate boundaries. Plate boundaries are classified by the way the plates are moving relative to each other: At a divergent boundary, two plates are moving away from each other. At a transform boundary, two plates are sliding past each other. At a convergent boundary, two plates are moving toward each other. One type of convergent boundary is an ocean-ocean subduction zone, which forms when two plates with oceanic crust move toward each other. One of the plates subducts, or sinks, below the other. When one of the plates subducts, a deep-sea trench forms at the plate boundary. Some rock in the subducting plate melts into magma and rises toward the surface. The magma cools and hardens to create a string of volcanoes in the ocean called a volcanic island arc.

To figure out what type of plate boundary formed the Japan Trench, you need to know how the tectonic plates interacted. To find this out, read the passage carefully. The Japan Trench is a deep-sea trench east of the islands of Japan. The trench formed as the Pacific Plate subducted, or sank, below the Okhotsk Plate. The two plates continue to move toward each other. This movement can cause devastating earthquakes in Japan, such as a magnitude 9.0 earthquake that occurred on March 11, 2011. The underlined part of the passage explains that the Japan Trench formed as the two plates moved toward each other. So, the Japan Trench formed at a convergent boundary.

The outer layer of Earth is broken up into many pieces called tectonic plates, or simply plates. The breaks between plates are called plate boundaries. Plate boundaries are classified by the way the plates are moving relative to each other: At a divergent boundary, two plates are moving away from each other. At a transform boundary, two plates are sliding past each other. At a convergent boundary, two plates are moving toward each other. One type of convergent boundary is an ocean-ocean subduction zone, which forms when two plates with oceanic crust move toward each other. One of the plates subducts, or sinks, below the other. When one of the plates subducts, a deep-sea trench forms at the plate boundary. Some rock in the subducting plate melts into magma and rises toward the surface. The magma cools and hardens to create a string of volcanoes in the ocean called a volcanic island arc. To figure out what type of plate boundary formed the Japan Trench, you need to know how the tectonic plates interacted. To find this out, read the passage carefully. The Japan Trench is a deep-sea trench east of the islands of Japan. The trench formed as the Pacific Plate subducted, or sank, below the Okhotsk Plate. The two plates continue to move toward each other. This movement can cause devastating earthquakes in Japan, such as a magnitude 9.0 earthquake that occurred on March 11, 2011. The underlined part of the passage explains that the Japan Trench formed as the two plates moved toward each other. So, the Japan Trench formed at a convergent boundary.

convergent

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Where are spores released from?

natural science

Fern plants reproduce using both asexual reproduction and sexual reproduction. Mature ferns have flat leaves called fronds. Ferns have structures that look like small dots on the underside of their fronds. These structures are called spore cases. The mature ferns use asexual reproduction to make spores. When the spore cases open, the spores are released. When a spore lands on the ground and germinates, it grows into a small heart-shaped plant. The heart-shaped plant begins the fern's sexual reproduction stage by making eggs and sperm. Ferns live in damp environments, and sperm can swim though small water drops. Self-fertilization happens when a sperm swims to an egg on the same heart-shaped plant. Cross-fertilization happens when the sperm swims to an egg on a nearby plant. Fertilization happens when a sperm and an egg fuse. The fertilized egg germinates and grows into a mature fern. The mature fern can make spores and begin the fern life cycle again.

Mature ferns have spore cases on the underside of their fronds. Spores are released from the spore cases. Heart-shaped plants produce eggs and sperm, not spores.

Fern plants reproduce using both asexual reproduction and sexual reproduction. Mature ferns have flat leaves called fronds. Ferns have structures that look like small dots on the underside of their fronds. These structures are called spore cases. The mature ferns use asexual reproduction to make spores. When the spore cases open, the spores are released. When a spore lands on the ground and germinates, it grows into a small heart-shaped plant. The heart-shaped plant begins the fern's sexual reproduction stage by making eggs and sperm. Ferns live in damp environments, and sperm can swim though small water drops. Self-fertilization happens when a sperm swims to an egg on the same heart-shaped plant. Cross-fertilization happens when the sperm swims to an egg on a nearby plant. Fertilization happens when a sperm and an egg fuse. The fertilized egg germinates and grows into a mature fern. The mature fern can make spores and begin the fern life cycle again. Mature ferns have spore cases on the underside of their fronds. Spores are released from the spore cases. Heart-shaped plants produce eggs and sperm, not spores.

spore cases on a mature fern

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Which animal's mouth is also adapted for gnawing?

natural science

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The shape of an animal's mouth is one example of an adaptation. Animals' mouths can be adapted in different ways. For example, a large mouth with sharp teeth might help an animal tear through meat. A long, thin mouth might help an animal catch insects that live in holes. Animals that eat similar food often have similar mouths.

Look at the picture of the Damara mole rat. The Damara mole rat has large front teeth. Its mouth is adapted for gnawing. The large front teeth can help the Damara mole rat break off pieces of food that it can swallow. Now look at each animal. Figure out which animal has a similar adaptation. The nutria has large front teeth. Its mouth is adapted for gnawing. The aardvark has a long tube-shaped mouth and a few, small teeth. Its mouth is not adapted for gnawing. The aardvark uses its mouth to get insects out of holes and burrows.

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The shape of an animal's mouth is one example of an adaptation. Animals' mouths can be adapted in different ways. For example, a large mouth with sharp teeth might help an animal tear through meat. A long, thin mouth might help an animal catch insects that live in holes. Animals that eat similar food often have similar mouths. Look at the picture of the Damara mole rat. The Damara mole rat has large front teeth. Its mouth is adapted for gnawing. The large front teeth can help the Damara mole rat break off pieces of food that it can swallow. Now look at each animal. Figure out which animal has a similar adaptation. The nutria has large front teeth. Its mouth is adapted for gnawing. The aardvark has a long tube-shaped mouth and a few, small teeth. Its mouth is not adapted for gnawing. The aardvark uses its mouth to get insects out of holes and burrows.

nutria

a1fbc0f3446a47d0b512c983a8df0617

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is weaker when the magnets are farther apart.

Distance affects the strength of the magnetic force. When magnets are farther apart, the magnetic force between them is weaker. The magnets in Pair 2 are farther apart than the magnets in Pair 1. So, the magnetic force is weaker in Pair 2 than in Pair 1.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is weaker when the magnets are farther apart. Distance affects the strength of the magnetic force. When magnets are farther apart, the magnetic force between them is weaker. The magnets in Pair 2 are farther apart than the magnets in Pair 1. So, the magnetic force is weaker in Pair 2 than in Pair 1.

The magnetic force is weaker in Pair 2.

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S). Here are some examples of magnets. Their poles are shown in different colors and labeled. Whether a magnet attracts or repels other magnets depends on the positions of its poles. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

To predict if these magnets will attract or repel, look at which poles are closest to each other. Both poles of each magnet line up with both poles of the other magnet. The south pole of each magnet is closest to the south pole of the other magnet. Like poles repel. So, these magnets will repel each other.

Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S). Here are some examples of magnets. Their poles are shown in different colors and labeled. Whether a magnet attracts or repels other magnets depends on the positions of its poles. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. To predict if these magnets will attract or repel, look at which poles are closest to each other. Both poles of each magnet line up with both poles of the other magnet. The south pole of each magnet is closest to the south pole of the other magnet. Like poles repel. So, these magnets will repel each other.

repel

9b7108fef4314bb1afef9d81b77453af

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Is the following statement about our solar system true or false? Half of the planets are made mainly of gas or ice.

natural science

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice.

The table tells you that of the eight planets, two are made mainly of gas and two are made mainly of ice. So, four of the eight, or half, of the planets are made mainly of gas or ice.

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The table tells you that of the eight planets, two are made mainly of gas and two are made mainly of ice. So, four of the eight, or half, of the planets are made mainly of gas or ice.

true

3702070d0c6543a8b7aa516f15b3ba94

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Compare the average kinetic energies of the particles in each sample. Which sample has the higher temperature?

natural science

The temperature of a substance depends on the average kinetic energy of the particles in the substance. The higher the average kinetic energy of the particles, the higher the temperature of the substance. The kinetic energy of a particle is determined by its mass and speed. For a pure substance, the greater the mass of each particle in the substance and the higher the average speed of the particles, the higher their average kinetic energy.

Each particle in the two samples has the same mass, and the particles in both samples have the same average speed. So, the particles in both samples have the same average kinetic energy. Because the particles in both samples have the same average kinetic energy, the samples must have the same temperature.

The temperature of a substance depends on the average kinetic energy of the particles in the substance. The higher the average kinetic energy of the particles, the higher the temperature of the substance. The kinetic energy of a particle is determined by its mass and speed. For a pure substance, the greater the mass of each particle in the substance and the higher the average speed of the particles, the higher their average kinetic energy. Each particle in the two samples has the same mass, and the particles in both samples have the same average speed. So, the particles in both samples have the same average kinetic energy. Because the particles in both samples have the same average kinetic energy, the samples must have the same temperature.

neither; the samples have the same temperature

d353e720668a4ebd84d68cd09a80c49b

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Which of these states is farthest north?

social science

Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map.

To find the answer, look at the compass rose. Look at which way the north arrow is pointing. Maine is farthest north.

Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map. To find the answer, look at the compass rose. Look at which way the north arrow is pointing. Maine is farthest north.

Maine

6420780929bf478b84f44381cd5ddfa4

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Which i in row C?

social science

A grid is made up of lines of squares. They are organized in rows and columns. A grid can help you use a map. A row is a line of squares that goes from side to side. Rows are marked with letters. A column is a line of squares that goes up and down. Columns are marked with numbers.

The fast-food restaurant is in row C.

A grid is made up of lines of squares. They are organized in rows and columns. A grid can help you use a map. A row is a line of squares that goes from side to side. Rows are marked with letters. A column is a line of squares that goes up and down. Columns are marked with numbers. The fast-food restaurant is in row C.

the fast-food restaurant

ab5c960d08764e369f2fed614c50cd0c

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Which of the following fossils is younger? Select the more likely answer.

natural science

A fossil is the preserved evidence of an ancient organism. Some fossils are formed from body parts such as bones or shells. Other fossils, such as footprints or burrows, are formed from traces of an organism's activities. Fossils are typically found in sedimentary rocks. Sedimentary rocks usually form in layers. Over time, new layers are added on top of old layers in a series called a rock sequence. The layers in an undisturbed rock sequence are in the same order as when they formed. So, the deeper layers are older than the shallower layers. The relative ages of fossils can be determined from their positions in an undisturbed rock sequence. Older fossils are usually in deeper layers, and younger fossils are usually in shallower layers.

Look again at the fossils in the rock sequence diagram. Compare the positions of these fossils to determine which one is younger: The crocodile egg fossil is in a shallower layer in the rock sequence than the feather fossil. So, the crocodile egg fossil is most likely younger than the feather fossil.

A fossil is the preserved evidence of an ancient organism. Some fossils are formed from body parts such as bones or shells. Other fossils, such as footprints or burrows, are formed from traces of an organism's activities. Fossils are typically found in sedimentary rocks. Sedimentary rocks usually form in layers. Over time, new layers are added on top of old layers in a series called a rock sequence. The layers in an undisturbed rock sequence are in the same order as when they formed. So, the deeper layers are older than the shallower layers. The relative ages of fossils can be determined from their positions in an undisturbed rock sequence. Older fossils are usually in deeper layers, and younger fossils are usually in shallower layers. Look again at the fossils in the rock sequence diagram. Compare the positions of these fossils to determine which one is younger: The crocodile egg fossil is in a shallower layer in the rock sequence than the feather fossil. So, the crocodile egg fossil is most likely younger than the feather fossil.

crocodile egg

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Select the chemical formula for this molecule.

natural science

Every substance around you is made up of atoms. Atoms can link together to form molecules. The links between atoms in a molecule are called chemical bonds. Different molecules are made up of different chemical elements, or types of atoms, bonded together. Scientists use both ball-and-stick models and chemical formulas to represent molecules. A ball-and-stick model of a molecule is shown below. The balls represent atoms. The sticks represent the chemical bonds between the atoms. Balls that are different colors represent atoms of different elements. The element that each color represents is shown in the legend. Every element has its own abbreviation, called its atomic symbol. Every chemical element is represented by its own symbol. For some elements, that symbol is one capital letter. For other elements, it is one capital letter followed by one lowercase letter. For example, the symbol for the element boron is B and the symbol for the element chlorine is Cl. The molecule shown above has one boron atom and three chlorine atoms. A chemical bond links each chlorine atom to the boron atom. The chemical formula for a substance contains the atomic symbol for each element in the substance. Many chemical formulas also contain subscripts. A subscript is small text placed lower than the normal line of text. Each subscript in a chemical formula is placed after the symbol for an element and tells you how many atoms of that element that symbol represents. If there is no subscript after a symbol, that symbol represents one atom. So, the chemical formula for a substance tells you which elements make up that substance. It also tells you the ratio of the atoms of those elements in the substance. For example, the chemical formula below tells you that there are three chlorine atoms for every one boron atom in the substance. This chemical formula represents the same substance as the ball-and-stick model shown above.

H is the symbol for hydrogen. According to the legend, hydrogen atoms are shown in light gray. O is the symbol for oxygen. According to the legend, oxygen atoms are shown in red. This ball-and-stick model shows a molecule with two hydrogen atoms and two oxygen atoms. The chemical formula will contain the symbols H and O. There are two hydrogen atoms, so H will have a subscript of 2. There are two oxygen atoms, so O will have a subscript of 2. The correct formula is H2 O2. The diagram below shows how each part of the chemical formula matches with each part of the model above.

Every substance around you is made up of atoms. Atoms can link together to form molecules. The links between atoms in a molecule are called chemical bonds. Different molecules are made up of different chemical elements, or types of atoms, bonded together. Scientists use both ball-and-stick models and chemical formulas to represent molecules. A ball-and-stick model of a molecule is shown below. The balls represent atoms. The sticks represent the chemical bonds between the atoms. Balls that are different colors represent atoms of different elements. The element that each color represents is shown in the legend. Every element has its own abbreviation, called its atomic symbol. Every chemical element is represented by its own symbol. For some elements, that symbol is one capital letter. For other elements, it is one capital letter followed by one lowercase letter. For example, the symbol for the element boron is B and the symbol for the element chlorine is Cl. The molecule shown above has one boron atom and three chlorine atoms. A chemical bond links each chlorine atom to the boron atom. The chemical formula for a substance contains the atomic symbol for each element in the substance. Many chemical formulas also contain subscripts. A subscript is small text placed lower than the normal line of text. Each subscript in a chemical formula is placed after the symbol for an element and tells you how many atoms of that element that symbol represents. If there is no subscript after a symbol, that symbol represents one atom. So, the chemical formula for a substance tells you which elements make up that substance. It also tells you the ratio of the atoms of those elements in the substance. For example, the chemical formula below tells you that there are three chlorine atoms for every one boron atom in the substance. This chemical formula represents the same substance as the ball-and-stick model shown above. H is the symbol for hydrogen. According to the legend, hydrogen atoms are shown in light gray. O is the symbol for oxygen. According to the legend, oxygen atoms are shown in red. This ball-and-stick model shows a molecule with two hydrogen atoms and two oxygen atoms. The chemical formula will contain the symbols H and O. There are two hydrogen atoms, so H will have a subscript of 2. There are two oxygen atoms, so O will have a subscript of 2. The correct formula is H2 O2. The diagram below shows how each part of the chemical formula matches with each part of the model above.

H2O2

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Pollinators move pollen from one part of a flower to another. Where does a pollinator pick up pollen?

natural science

Flowering plants, called angiosperms, use their flowers for sexual reproduction. Flowers can have male parts, female parts, or both! The male part is called the stamen, and the female part is called the pistil. Both the male and female parts are needed for sexual reproduction. The female part produces eggs, and the male part produces pollen. Pollen contains cells that become sperm. Pollination happens when pollen lands on top of the pistil. Self-pollination happens when a plant with both male and female parts pollinates itself. Cross-pollination happens when pollen from one plant lands on the pistil of a flower on a different plant. Animals, including birds and insects, can be pollinators. Many pollinators come to flowers to get food. As a pollinator feeds, it moves pollen from one flower to another. After pollination, sperm from the pollen fuse with eggs. This is called fertilization. The fertilized eggs then grow into seeds. When a seed lands on the ground, it can germinate and grow into a new plant. The new plant can grow flowers and begin the angiosperm plant life cycle again.

Anthers make pollen. When a pollinator brushes against the anthers, pollen might stick to the pollinator. A pollinator may drop pollen on the pistil. This is called pollination. But a pollinator does not pick up pollen from the pistil.

Flowering plants, called angiosperms, use their flowers for sexual reproduction. Flowers can have male parts, female parts, or both! The male part is called the stamen, and the female part is called the pistil. Both the male and female parts are needed for sexual reproduction. The female part produces eggs, and the male part produces pollen. Pollen contains cells that become sperm. Pollination happens when pollen lands on top of the pistil. Self-pollination happens when a plant with both male and female parts pollinates itself. Cross-pollination happens when pollen from one plant lands on the pistil of a flower on a different plant. Animals, including birds and insects, can be pollinators. Many pollinators come to flowers to get food. As a pollinator feeds, it moves pollen from one flower to another. After pollination, sperm from the pollen fuse with eggs. This is called fertilization. The fertilized eggs then grow into seeds. When a seed lands on the ground, it can germinate and grow into a new plant. The new plant can grow flowers and begin the angiosperm plant life cycle again. Anthers make pollen. When a pollinator brushes against the anthers, pollen might stick to the pollinator. A pollinator may drop pollen on the pistil. This is called pollination. But a pollinator does not pick up pollen from the pistil.

the anthers

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The north pole of each magnet is labeled N, and the south pole is labeled S. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

To predict if these magnets will attract or repel, look at which poles are closest to each other. The south pole of one magnet is closest to the south pole of the other magnet. Like poles repel. So, these magnets will repel each other.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The north pole of each magnet is labeled N, and the south pole is labeled S. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. To predict if these magnets will attract or repel, look at which poles are closest to each other. The south pole of one magnet is closest to the south pole of the other magnet. Like poles repel. So, these magnets will repel each other.

repel

2a78d89355d24219b018badd8fa2d182

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Which of these states is farthest north?

social science

Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map.

To find the answer, look at the compass rose. Look at which way the north arrow is pointing. Kansas is farthest north.

Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map. To find the answer, look at the compass rose. Look at which way the north arrow is pointing. Kansas is farthest north.

Kansas

9e9f4cfe56a24f6eb69e3610de4dc29e

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Is the water in a bathtub a solid or a liquid?

natural science

Solid and liquid are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a shape of its own. Some solids can be bent or broken easily. Others are hard to bend or break. A glass cup is a solid. A sock is also a solid. When matter is a liquid, it takes the shape of its container. Think about pouring a liquid from a cup into a bottle. The shape of the liquid is different in the cup than in the bottle. But the liquid still takes up the same amount of space. Juice is a liquid. Honey is also a liquid.

The water in a bathtub is a liquid. A liquid takes the shape of any container it is in. If you move the water from a bathtub into a different container, the water will take the shape of that container. But the water will still take up the same amount of space.

Solid and liquid are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a shape of its own. Some solids can be bent or broken easily. Others are hard to bend or break. A glass cup is a solid. A sock is also a solid. When matter is a liquid, it takes the shape of its container. Think about pouring a liquid from a cup into a bottle. The shape of the liquid is different in the cup than in the bottle. But the liquid still takes up the same amount of space. Juice is a liquid. Honey is also a liquid. The water in a bathtub is a liquid. A liquid takes the shape of any container it is in. If you move the water from a bathtub into a different container, the water will take the shape of that container. But the water will still take up the same amount of space.

a liquid

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Select the organism in the same genus as the bighorn sheep.

natural science

Scientists use scientific names to identify organisms. Scientific names are made of two words. The first word in an organism's scientific name tells you the organism's genus. A genus is a group of organisms that share many traits. A genus is made up of one or more species. A species is a group of very similar organisms. The second word in an organism's scientific name tells you its species within its genus. Together, the two parts of an organism's scientific name identify its species. For example Ursus maritimus and Ursus americanus are two species of bears. They are part of the same genus, Ursus. But they are different species within the genus. Ursus maritimus has the species name maritimus. Ursus americanus has the species name americanus. Both bears have small round ears and sharp claws. But Ursus maritimus has white fur and Ursus americanus has black fur.

A bighorn sheep's scientific name is Ovis canadensis. The first word of its scientific name is Ovis. Castor canadensis and Ovis canadensis are not in the same genus. These organisms are not in the same genus, but part of their scientific names is the same. Castor canadensis and Ovis canadensis have the same species name within their genus, canadensis. But the first words of their scientific names are different. Castor canadensis is in the genus Castor, and Ovis canadensis is in the genus Ovis. Strix nebulosa is in the genus Strix. The first word of its scientific name is Strix. So, Strix nebulosa and Ovis canadensis are not in the same genus. Ovis aries is in the genus Ovis. The first word of its scientific name is Ovis. So, Ovis aries and Ovis canadensis are in the same genus.

Scientists use scientific names to identify organisms. Scientific names are made of two words. The first word in an organism's scientific name tells you the organism's genus. A genus is a group of organisms that share many traits. A genus is made up of one or more species. A species is a group of very similar organisms. The second word in an organism's scientific name tells you its species within its genus. Together, the two parts of an organism's scientific name identify its species. For example Ursus maritimus and Ursus americanus are two species of bears. They are part of the same genus, Ursus. But they are different species within the genus. Ursus maritimus has the species name maritimus. Ursus americanus has the species name americanus. Both bears have small round ears and sharp claws. But Ursus maritimus has white fur and Ursus americanus has black fur. A bighorn sheep's scientific name is Ovis canadensis. The first word of its scientific name is Ovis. Castor canadensis and Ovis canadensis are not in the same genus. These organisms are not in the same genus, but part of their scientific names is the same. Castor canadensis and Ovis canadensis have the same species name within their genus, canadensis. But the first words of their scientific names are different. Castor canadensis is in the genus Castor, and Ovis canadensis is in the genus Ovis. Strix nebulosa is in the genus Strix. The first word of its scientific name is Strix. So, Strix nebulosa and Ovis canadensis are not in the same genus. Ovis aries is in the genus Ovis. The first word of its scientific name is Ovis. So, Ovis aries and Ovis canadensis are in the same genus.

Ovis aries

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Which statement describes the Białowieża Forest ecosystem?

natural science

An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there

A temperate deciduous forest is a type of ecosystem. Temperate deciduous forests have the following features: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. So, the following statements describe the Białowieża Forest ecosystem: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. It has only a few types of trees. It has warm, wet summers and cold, wet winters. The following statement does not describe the Białowieża Forest: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. It has a small amount of rain or snow.

An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there A temperate deciduous forest is a type of ecosystem. Temperate deciduous forests have the following features: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. So, the following statements describe the Białowieża Forest ecosystem: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. It has only a few types of trees. It has warm, wet summers and cold, wet winters. The following statement does not describe the Białowieża Forest: warm, wet summers and cold, wet winters, soil that is rich in nutrients, and only a few types of trees. It has a small amount of rain or snow.

It has only a few types of trees.

2f1eb71c2c2d44399f29bf9b950ef956

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Does this passage describe the weather or the climate?

natural science

The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere. Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day. Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures.

Read the passage carefully. The Dominican Republic has lush, green forests and beautiful beaches. Temperatures in the Dominican Republic are usually between 70°F and 90°F throughout the year. The underlined part of the passage tells you about the usual temperature pattern in the Dominican Republic. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.

The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere. Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day. Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures. Read the passage carefully. The Dominican Republic has lush, green forests and beautiful beaches. Temperatures in the Dominican Republic are usually between 70°F and 90°F throughout the year. The underlined part of the passage tells you about the usual temperature pattern in the Dominican Republic. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.

climate

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Which ocean is highlighted?

social science

Oceans are huge bodies of salt water. The world has five oceans. All of the oceans are connected, making one world ocean.

This is the Pacific Ocean.

Oceans are huge bodies of salt water. The world has five oceans. All of the oceans are connected, making one world ocean. This is the Pacific Ocean.

the Pacific Ocean

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Which animal's limbs are also adapted for gliding?

natural science

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. Arms, legs, flippers, and wings are different types of limbs. The type of limbs an animal has is an example of an adaptation. Animals' limbs can be adapted in different ways. For example, long legs might help an animal run fast. Flippers might help an animal swim. Wings might help an animal fly.

Look at the picture of the sugar glider. The sugar glider can spread its patagium like a wing. This helps it glide through the air from the higher branches of one tree to the lower branches of another tree. Now look at each animal. Figure out which animal has a similar adaptation. The Malayan colugo has a patagium stretched between its arms and legs. Its limbs are adapted for gliding. The Sumatran orangutan has long limbs but no patagium. Its limbs are not adapted for gliding. The Sumatran orangutan uses its limbs to climb trees.

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. Arms, legs, flippers, and wings are different types of limbs. The type of limbs an animal has is an example of an adaptation. Animals' limbs can be adapted in different ways. For example, long legs might help an animal run fast. Flippers might help an animal swim. Wings might help an animal fly. Look at the picture of the sugar glider. The sugar glider can spread its patagium like a wing. This helps it glide through the air from the higher branches of one tree to the lower branches of another tree. Now look at each animal. Figure out which animal has a similar adaptation. The Malayan colugo has a patagium stretched between its arms and legs. Its limbs are adapted for gliding. The Sumatran orangutan has long limbs but no patagium. Its limbs are not adapted for gliding. The Sumatran orangutan uses its limbs to climb trees.

Malayan colugo

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Which continent is highlighted?

social science

A continent is one of the seven largest areas of land on earth.

This continent is North America.

A continent is one of the seven largest areas of land on earth. This continent is North America.

North America

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Which better describes the Gran Sabana ecosystem?

natural science

An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there

A savanna grassland is a type of ecosystem. Savanna grasslands have the following features: warm summers and warm winters, a rainy season and a dry season, and soil that is poor in nutrients. So, the Gran Sabana has a rainy season and a dry season. It also has soil that is poor in nutrients.

An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there A savanna grassland is a type of ecosystem. Savanna grasslands have the following features: warm summers and warm winters, a rainy season and a dry season, and soil that is poor in nutrients. So, the Gran Sabana has a rainy season and a dry season. It also has soil that is poor in nutrients.

It has a rainy season and a dry season. It also has soil that is poor in nutrients.

8cf532c1fd4a4d62b8268b889406ab4b

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Which of these states is farthest west?

social science

Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map.

To find the answer, look at the compass rose. Look at which way the west arrow is pointing. Georgia is farthest west.

Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map. To find the answer, look at the compass rose. Look at which way the west arrow is pointing. Georgia is farthest west.

Georgia

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Select the bird below.

natural science

Birds, mammals, fish, reptiles, and amphibians are groups of animals. The animals in each group have traits in common. Scientists sort animals into groups based on traits they have in common. This process is called classification.

A koala is a mammal. It has fur and feeds its young milk. Koalas sleep for up to 20 hours a day! A white stork is a bird. It has feathers, two wings, and a beak. Storks wade in shallow water to look for food. Storks eat fish, insects, worms, and other small animals.

Birds, mammals, fish, reptiles, and amphibians are groups of animals. The animals in each group have traits in common. Scientists sort animals into groups based on traits they have in common. This process is called classification. A koala is a mammal. It has fur and feeds its young milk. Koalas sleep for up to 20 hours a day! A white stork is a bird. It has feathers, two wings, and a beak. Storks wade in shallow water to look for food. Storks eat fish, insects, worms, and other small animals.

white stork

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What is the expected ratio of offspring that have thorns to offspring that do not have thorns? Choose the most likely ratio.

natural science

Offspring phenotypes: dominant or recessive? How do you determine an organism's phenotype for a trait? Look at the combination of alleles in the organism's genotype for the gene that affects that trait. Some alleles have types called dominant and recessive. These two types can cause different versions of the trait to appear as the organism's phenotype. If an organism's genotype has at least one dominant allele for a gene, the organism's phenotype will be the dominant allele's version of the gene's trait. If an organism's genotype has only recessive alleles for a gene, the organism's phenotype will be the recessive allele's version of the gene's trait. A Punnett square shows what types of offspring a cross can produce. The expected ratio of offspring types compares how often the cross produces each type of offspring, on average. To write this ratio, count the number of boxes in the Punnett square representing each type. For example, consider the Punnett square below. | F | f F | FF | Ff f | Ff | ff There is 1 box with the genotype FF and 2 boxes with the genotype Ff. So, the expected ratio of offspring with the genotype FF to those with Ff is 1:2.

To determine how many boxes in the Punnett square represent offspring that do or do not have thorns, consider whether each phenotype is the dominant or recessive allele's version of the thorns trait. The question tells you that the R allele, which is for having thorns, is dominant over the r allele, which is for not having thorns. Having thorns is the dominant allele's version of the thorns trait. A rose plant with the dominant version of the thorns trait must have at least one dominant allele for the thorns gene. So, offspring that have thorns must have the genotype RR or Rr. There are 0 boxes in the Punnett square with the genotype RR or Rr. Not having thorns is the recessive allele's version of the thorns trait. A rose plant with the recessive version of the thorns trait must have only recessive alleles for the thorns gene. So, offspring that do not have thorns must have the genotype rr. All 4 boxes in the Punnett square have the genotype rr. So, the expected ratio of offspring that have thorns to offspring that do not have thorns is 0:4. This means that, based on the Punnett square, this cross will never produce offspring that have thorns. Instead, this cross is expected to always produce offspring that do not have thorns.

Offspring phenotypes: dominant or recessive? How do you determine an organism's phenotype for a trait? Look at the combination of alleles in the organism's genotype for the gene that affects that trait. Some alleles have types called dominant and recessive. These two types can cause different versions of the trait to appear as the organism's phenotype. If an organism's genotype has at least one dominant allele for a gene, the organism's phenotype will be the dominant allele's version of the gene's trait. If an organism's genotype has only recessive alleles for a gene, the organism's phenotype will be the recessive allele's version of the gene's trait. A Punnett square shows what types of offspring a cross can produce. The expected ratio of offspring types compares how often the cross produces each type of offspring, on average. To write this ratio, count the number of boxes in the Punnett square representing each type. For example, consider the Punnett square below. | F | f F | FF | Ff f | Ff | ff There is 1 box with the genotype FF and 2 boxes with the genotype Ff. So, the expected ratio of offspring with the genotype FF to those with Ff is 1:2. To determine how many boxes in the Punnett square represent offspring that do or do not have thorns, consider whether each phenotype is the dominant or recessive allele's version of the thorns trait. The question tells you that the R allele, which is for having thorns, is dominant over the r allele, which is for not having thorns. Having thorns is the dominant allele's version of the thorns trait. A rose plant with the dominant version of the thorns trait must have at least one dominant allele for the thorns gene. So, offspring that have thorns must have the genotype RR or Rr. There are 0 boxes in the Punnett square with the genotype RR or Rr. Not having thorns is the recessive allele's version of the thorns trait. A rose plant with the recessive version of the thorns trait must have only recessive alleles for the thorns gene. So, offspring that do not have thorns must have the genotype rr. All 4 boxes in the Punnett square have the genotype rr. So, the expected ratio of offspring that have thorns to offspring that do not have thorns is 0:4. This means that, based on the Punnett square, this cross will never produce offspring that have thorns. Instead, this cross is expected to always produce offspring that do not have thorns.

0:4

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Which better describes the Sonoran Desert ecosystem?

natural science

An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there

A hot desert is a type of ecosystem. Hot deserts have the following features: a small amount of rain, dry, thin soil, and many different types of organisms. So, the Sonoran Desert has a small amount of rain. It also has dry, thin soil.

An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there A hot desert is a type of ecosystem. Hot deserts have the following features: a small amount of rain, dry, thin soil, and many different types of organisms. So, the Sonoran Desert has a small amount of rain. It also has dry, thin soil.

It has a small amount of rain. It also has dry, thin soil.

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Which solution has a higher concentration of green particles?

natural science

A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent. The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent. concentration = particles of solute / volume of solvent

In Solution A and Solution B, the green particles represent the solute. To figure out which solution has a higher concentration of green particles, look at both the number of green particles and the volume of the solvent in each container. Use the concentration formula to find the number of green particles per milliliter. Solution B has more green particles per milliliter. So, Solution B has a higher concentration of green particles.

A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent. The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent. concentration = particles of solute / volume of solvent In Solution A and Solution B, the green particles represent the solute. To figure out which solution has a higher concentration of green particles, look at both the number of green particles and the volume of the solvent in each container. Use the concentration formula to find the number of green particles per milliliter. Solution B has more green particles per milliliter. So, Solution B has a higher concentration of green particles.

Solution B

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Which property do these four objects have in common?

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification.

Look at each object. For each object, decide if it has that property. A lemon has a sour taste. The wet ice cube is not sour. A shiny object reflects a lot of light. You can usually see your reflection in a shiny object. The marbles are shiny, but the horseshoe is not. A hard object does not change shape when pressed or squeezed. All four objects are hard. The property that all four objects have in common is hard.

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it. Different objects can have properties in common. You can use these properties to put objects into groups. Grouping objects by their properties is called classification. Look at each object. For each object, decide if it has that property. A lemon has a sour taste. The wet ice cube is not sour. A shiny object reflects a lot of light. You can usually see your reflection in a shiny object. The marbles are shiny, but the horseshoe is not. A hard object does not change shape when pressed or squeezed. All four objects are hard. The property that all four objects have in common is hard.

hard

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The north pole of each magnet is labeled N, and the south pole is labeled S. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. Whether a magnet attracts or repels other magnets depends on the positions of its poles, or ends. Every magnet has two poles: north and south. Here are some examples of magnets. The north pole of each magnet is labeled N, and the south pole is labeled S. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.

repel

c3cb7045be794478bb51fd8fa1122af9

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Is the following statement about our solar system true or false? The volume of Uranus is less than ten times the volume of Neptune.

natural science

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For example, the volume of Jupiter is 1,430,000,000,000,000 km^3. In scientific notation, Jupiter's volume is written as 1.43 x 10^15 km^3. To compare two numbers written in scientific notation, first compare their exponents. The bigger the exponent is, the bigger the number is. For example: 1.43 x 10^15 is larger than 1.43 x 10^12 If their exponents are equal, compare the first numbers. For example: 1.43 x 10^15 is larger than 1.25 x 10^15 To multiply a number written in scientific notation by a power of 10, write the multiple of 10 as 10 raised to an exponent. Then, add the exponents. For example: 1.43 x 10^15 · 1000 = 1.43 x 10^15 · 10^3 = 1.43 x 10^(15 + 3) = 1.43 x 10^18

To determine if this statement is true, calculate the value of ten times the volume of Neptune. Then compare the result to the volume of Uranus. The volume of Uranus is 6.83 x 10^13 km^3, which is less than 6.25 x 10^14 km^3. So, the volume of Uranus is less than ten times the volume of Neptune.

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For example, the volume of Jupiter is 1,430,000,000,000,000 km^3. In scientific notation, Jupiter's volume is written as 1.43 x 10^15 km^3. To compare two numbers written in scientific notation, first compare their exponents. The bigger the exponent is, the bigger the number is. For example: 1.43 x 10^15 is larger than 1.43 x 10^12 If their exponents are equal, compare the first numbers. For example: 1.43 x 10^15 is larger than 1.25 x 10^15 To multiply a number written in scientific notation by a power of 10, write the multiple of 10 as 10 raised to an exponent. Then, add the exponents. For example: 1.43 x 10^15 · 1000 = 1.43 x 10^15 · 10^3 = 1.43 x 10^(15 + 3) = 1.43 x 10^18 To determine if this statement is true, calculate the value of ten times the volume of Neptune. Then compare the result to the volume of Uranus. The volume of Uranus is 6.83 x 10^13 km^3, which is less than 6.25 x 10^14 km^3. So, the volume of Uranus is less than ten times the volume of Neptune.

true

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Will these magnets attract or repel each other?

natural science

Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S). Here are some examples of magnets. Their poles are shown in different colors and labeled. Whether a magnet attracts or repels other magnets depends on the positions of its poles. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel.

To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.

Magnets can pull or push on other magnets without touching them. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes are called magnetic forces. Magnetic forces are strongest at the magnets' poles, or ends. Every magnet has two poles: a north pole (N) and a south pole (S). Here are some examples of magnets. Their poles are shown in different colors and labeled. Whether a magnet attracts or repels other magnets depends on the positions of its poles. If opposite poles are closest to each other, the magnets attract. The magnets in the pair below attract. If the same, or like, poles are closest to each other, the magnets repel. The magnets in both pairs below repel. To predict if these magnets will attract or repel, look at which poles are closest to each other. The north pole of one magnet is closest to the north pole of the other magnet. Like poles repel. So, these magnets will repel each other.

repel

778925b1a4f54ffa88ae354605ad41c6

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is weaker when the magnets are farther apart.

Distance affects the strength of the magnetic force. When magnets are farther apart, the magnetic force between them is weaker. The magnets in Pair 1 are farther apart than the magnets in Pair 2. So, the magnetic force is weaker in Pair 1 than in Pair 2.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is weaker when the magnets are farther apart. Distance affects the strength of the magnetic force. When magnets are farther apart, the magnetic force between them is weaker. The magnets in Pair 1 are farther apart than the magnets in Pair 2. So, the magnetic force is weaker in Pair 1 than in Pair 2.

The magnetic force is weaker in Pair 1.

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Does Polytrichum commune have cells that have a nucleus?

natural science

In the past, scientists classified living organisms into two groups: plants and animals. Over the past 300 years, scientists have discovered many more types of organisms. Today, many scientists classify organisms into six broad groups, called kingdoms. Organisms in each kingdom have specific traits. The table below shows some traits used to describe each kingdom. | Bacteria | Archaea | Protists | Fungi | Animals | Plants How many cells do they have? | one | one | one or many | one or many | many | many Do their cells have a nucleus? | no | no | yes | yes | yes | yes Can their cells make food? | some species can | some species can | some species can | no | no | yes

Polytrichum commune is a plant. Plant cells have a nucleus.

In the past, scientists classified living organisms into two groups: plants and animals. Over the past 300 years, scientists have discovered many more types of organisms. Today, many scientists classify organisms into six broad groups, called kingdoms. Organisms in each kingdom have specific traits. The table below shows some traits used to describe each kingdom. | Bacteria | Archaea | Protists | Fungi | Animals | Plants How many cells do they have? | one | one | one or many | one or many | many | many Do their cells have a nucleus? | no | no | yes | yes | yes | yes Can their cells make food? | some species can | some species can | some species can | no | no | yes Polytrichum commune is a plant. Plant cells have a nucleus.

yes

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Which is the main persuasive appeal used in this ad?

language science

The purpose of an advertisement is to persuade people to do something. To accomplish this purpose, advertisements use three types of persuasive strategies, or appeals: Appeals to ethos, or character, show that the writer or speaker is trustworthy or is an authority on a subject. An ad that appeals to ethos might do one of the following: say that a brand has been trusted for many years note that a brand is recommended by a respected organization or celebrity include a quote from a "real person" who shares the audience's values Appeals to logos, or reason, use logic and specific evidence. An ad that appeals to logos might do one of the following: use graphs or charts to display information mention the results of scientific studies explain the science behind a product or service Appeals to pathos, or emotion, use feelings rather than facts to persuade the audience. An ad that appeals to pathos might do one of the following: trigger a fear, such as the fear of embarrassment appeal to a desire, such as the desire to appear attractive link the product to a positive feeling, such as adventure, love, or luxury

The ad appeals to ethos, or character. It notes that the brand is trusted by hospitals.

The purpose of an advertisement is to persuade people to do something. To accomplish this purpose, advertisements use three types of persuasive strategies, or appeals: Appeals to ethos, or character, show that the writer or speaker is trustworthy or is an authority on a subject. An ad that appeals to ethos might do one of the following: say that a brand has been trusted for many years note that a brand is recommended by a respected organization or celebrity include a quote from a "real person" who shares the audience's values Appeals to logos, or reason, use logic and specific evidence. An ad that appeals to logos might do one of the following: use graphs or charts to display information mention the results of scientific studies explain the science behind a product or service Appeals to pathos, or emotion, use feelings rather than facts to persuade the audience. An ad that appeals to pathos might do one of the following: trigger a fear, such as the fear of embarrassment appeal to a desire, such as the desire to appear attractive link the product to a positive feeling, such as adventure, love, or luxury The ad appeals to ethos, or character. It notes that the brand is trusted by hospitals.

ethos (character)

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Is the following statement about our solar system true or false? Jupiter's volume is more than ten times as large as Saturn's volume.

natural science

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For example, the volume of Jupiter is 1,430,000,000,000,000 km^3. In scientific notation, Jupiter's volume is written as 1.43 x 10^15 km^3. To compare two numbers written in scientific notation, first compare their exponents. The bigger the exponent is, the bigger the number is. For example: 1.43 x 10^15 is larger than 1.43 x 10^12 If their exponents are equal, compare the first numbers. For example: 1.43 x 10^15 is larger than 1.25 x 10^15 To multiply a number written in scientific notation by a power of 10, write the multiple of 10 as 10 raised to an exponent. Then, add the exponents. For example: 1.43 x 10^15 · 1000 = 1.43 x 10^15 · 10^3 = 1.43 x 10^(15 + 3) = 1.43 x 10^18

To determine if this statement is true, calculate the value of ten times the volume of Saturn. Then compare the result to the volume of Jupiter. The volume of Jupiter is 1.43 x 10^15 km^3, which is less than 8.27 x 10^15 km^3. So, Jupiter's volume is less than ten times as large as Saturn's volume.

A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For example, the volume of Jupiter is 1,430,000,000,000,000 km^3. In scientific notation, Jupiter's volume is written as 1.43 x 10^15 km^3. To compare two numbers written in scientific notation, first compare their exponents. The bigger the exponent is, the bigger the number is. For example: 1.43 x 10^15 is larger than 1.43 x 10^12 If their exponents are equal, compare the first numbers. For example: 1.43 x 10^15 is larger than 1.25 x 10^15 To multiply a number written in scientific notation by a power of 10, write the multiple of 10 as 10 raised to an exponent. Then, add the exponents. For example: 1.43 x 10^15 · 1000 = 1.43 x 10^15 · 10^3 = 1.43 x 10^(15 + 3) = 1.43 x 10^18 To determine if this statement is true, calculate the value of ten times the volume of Saturn. Then compare the result to the volume of Jupiter. The volume of Jupiter is 1.43 x 10^15 km^3, which is less than 8.27 x 10^15 km^3. So, Jupiter's volume is less than ten times as large as Saturn's volume.

false

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Which is this organism's scientific name?

natural science

An organism's common name is the name that people normally call the organism. Common names often contain words you know. An organism's scientific name is the name scientists use to identify the organism. Scientific names often contain words that are not used in everyday English. Scientific names are written in italics, but common names are usually not. The first word of the scientific name is capitalized, and the second word is not. For example, the common name of the animal below is giant panda. Its scientific name is Ailuropoda melanoleuca.

Galeocerdo cuvier is written in italics. The first word is capitalized, and the second word is not. So, Galeocerdo cuvier is the scientific name.

An organism's common name is the name that people normally call the organism. Common names often contain words you know. An organism's scientific name is the name scientists use to identify the organism. Scientific names often contain words that are not used in everyday English. Scientific names are written in italics, but common names are usually not. The first word of the scientific name is capitalized, and the second word is not. For example, the common name of the animal below is giant panda. Its scientific name is Ailuropoda melanoleuca. Galeocerdo cuvier is written in italics. The first word is capitalized, and the second word is not. So, Galeocerdo cuvier is the scientific name.

Galeocerdo cuvier

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Select the mammal below.

natural science

Birds, mammals, fish, reptiles, and amphibians are groups of animals. Scientists sort animals into each group based on traits they have in common. This process is called classification. Classification helps scientists learn about how animals live. Classification also helps scientists compare similar animals.

A poison dart frog is an amphibian. It has moist skin and begins its life in water. Poison dart frogs come in many bright colors. Their bright color warns other animals that these frogs are poisonous. A mandarinfish is a fish. It lives underwater. It has fins, not limbs. Mandarinfish often live near coral reefs. They eat small worms, snails, and fish eggs. A fire salamander is an amphibian. It has moist skin and begins its life in water. Fire salamanders can release poison from their skin. This poison helps protect them from predators. A Canadian lynx is a mammal. It has fur and feeds its young milk. Canadian lynx have padded feet to help them walk on snow.

Birds, mammals, fish, reptiles, and amphibians are groups of animals. Scientists sort animals into each group based on traits they have in common. This process is called classification. Classification helps scientists learn about how animals live. Classification also helps scientists compare similar animals. A poison dart frog is an amphibian. It has moist skin and begins its life in water. Poison dart frogs come in many bright colors. Their bright color warns other animals that these frogs are poisonous. A mandarinfish is a fish. It lives underwater. It has fins, not limbs. Mandarinfish often live near coral reefs. They eat small worms, snails, and fish eggs. A fire salamander is an amphibian. It has moist skin and begins its life in water. Fire salamanders can release poison from their skin. This poison helps protect them from predators. A Canadian lynx is a mammal. It has fur and feeds its young milk. Canadian lynx have padded feet to help them walk on snow.

Canadian lynx

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other.

Distance affects the strength of the magnetic force. But the distance between the magnets in Pair 1 and in Pair 2 is the same. So, the strength of the magnetic force is the same in both pairs.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. Distance affects the strength of the magnetic force. But the distance between the magnets in Pair 1 and in Pair 2 is the same. So, the strength of the magnetic force is the same in both pairs.

The strength of the magnetic force is the same in both pairs.

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Is magma a solid, a liquid, or a gas?

natural science

Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own. Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid. When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle. Some liquids are thicker than others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk. When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space. Many gases are invisible. The oxygen you breathe is a gas. The helium in a balloon is also a gas.

Magma is a liquid. A liquid can change shape. But it still takes up the same amount of space. Magma is melted rock. Rock is usually a solid. But when it gets hot enough, it can melt! Unlike solid rock, magma can change shape easily and flow.

Solid, liquid, and gas are states of matter. Matter is anything that takes up space. Matter can come in different states, or forms. When matter is a solid, it has a definite volume and a definite shape. So, a solid has a size and shape of its own. Some solids can be easily folded, bent, or broken. A piece of paper is a solid. Also, some solids are very small. A grain of sand is a solid. When matter is a liquid, it has a definite volume but not a definite shape. So, a liquid has a size of its own, but it does not have a shape of its own. Think about pouring juice from a bottle into a cup. The juice still takes up the same amount of space, but it takes the shape of the bottle. Some liquids are thicker than others. Honey and milk are both liquids. But pouring honey takes more time than pouring milk. When matter is a gas, it does not have a definite volume or a definite shape. A gas expands, or gets bigger, until it completely fills a space. A gas can also get smaller if it is squeezed into a smaller space. Many gases are invisible. The oxygen you breathe is a gas. The helium in a balloon is also a gas. Magma is a liquid. A liquid can change shape. But it still takes up the same amount of space. Magma is melted rock. Rock is usually a solid. But when it gets hot enough, it can melt! Unlike solid rock, magma can change shape easily and flow.

a liquid

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Select the organism in the same genus as the cocoi heron.

natural science

Scientists use scientific names to identify organisms. Scientific names are made of two words. The first word in an organism's scientific name tells you the organism's genus. A genus is a group of organisms that share many traits. A genus is made up of one or more species. A species is a group of very similar organisms. The second word in an organism's scientific name tells you its species within its genus. Together, the two parts of an organism's scientific name identify its species. For example Ursus maritimus and Ursus americanus are two species of bears. They are part of the same genus, Ursus. But they are different species within the genus. Ursus maritimus has the species name maritimus. Ursus americanus has the species name americanus. Both bears have small round ears and sharp claws. But Ursus maritimus has white fur and Ursus americanus has black fur.

A cocoi heron's scientific name is Ardea cocoi. The first word of its scientific name is Ardea. Ardea herodias is in the genus Ardea. The first word of its scientific name is Ardea. So, Ardea herodias and Ardea cocoi are in the same genus. Strix uralensis is in the genus Strix. The first word of its scientific name is Strix. So, Strix uralensis and Ardea cocoi are not in the same genus. Pelecanus occidentalis is in the genus Pelecanus. The first word of its scientific name is Pelecanus. So, Pelecanus occidentalis and Ardea cocoi are not in the same genus.

Scientists use scientific names to identify organisms. Scientific names are made of two words. The first word in an organism's scientific name tells you the organism's genus. A genus is a group of organisms that share many traits. A genus is made up of one or more species. A species is a group of very similar organisms. The second word in an organism's scientific name tells you its species within its genus. Together, the two parts of an organism's scientific name identify its species. For example Ursus maritimus and Ursus americanus are two species of bears. They are part of the same genus, Ursus. But they are different species within the genus. Ursus maritimus has the species name maritimus. Ursus americanus has the species name americanus. Both bears have small round ears and sharp claws. But Ursus maritimus has white fur and Ursus americanus has black fur. A cocoi heron's scientific name is Ardea cocoi. The first word of its scientific name is Ardea. Ardea herodias is in the genus Ardea. The first word of its scientific name is Ardea. So, Ardea herodias and Ardea cocoi are in the same genus. Strix uralensis is in the genus Strix. The first word of its scientific name is Strix. So, Strix uralensis and Ardea cocoi are not in the same genus. Pelecanus occidentalis is in the genus Pelecanus. The first word of its scientific name is Pelecanus. So, Pelecanus occidentalis and Ardea cocoi are not in the same genus.

Ardea herodias

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Which bird's beak is also adapted to catch insects?

natural science

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The shape of a bird's beak is one example of an adaptation. Birds' beaks can be adapted in different ways. For example, a sharp hooked beak might help a bird tear through meat easily. A short, thick beak might help a bird break through a seed's hard shell. Birds that eat similar food often have similar beaks.

Look at the picture of the common nighthawk. A short, thin beak is light and easy to move. The common nighthawk uses its beak to grab fast-moving insects while flying. Now look at each bird. Figure out which bird has a similar adaptation. The black-capped chickadee has a short, thin beak. Its beak is adapted to catch insects. The military macaw has a thick hooked beak. Its beak is not adapted to catch insects. The military macaw uses its beak to crack open large, hard nuts.

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The shape of a bird's beak is one example of an adaptation. Birds' beaks can be adapted in different ways. For example, a sharp hooked beak might help a bird tear through meat easily. A short, thick beak might help a bird break through a seed's hard shell. Birds that eat similar food often have similar beaks. Look at the picture of the common nighthawk. A short, thin beak is light and easy to move. The common nighthawk uses its beak to grab fast-moving insects while flying. Now look at each bird. Figure out which bird has a similar adaptation. The black-capped chickadee has a short, thin beak. Its beak is adapted to catch insects. The military macaw has a thick hooked beak. Its beak is not adapted to catch insects. The military macaw uses its beak to crack open large, hard nuts.

black-capped chickadee

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Think about the magnetic force between the magnets in each pair. Which of the following statements is true?

natural science

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the magnitude of a magnetic force between two magnets by changing the distance between them. The magnitude of the magnetic force is smaller when there is a greater distance between the magnets.

Distance affects the magnitude of the magnetic force. When there is a greater distance between magnets, the magnitude of the magnetic force between them is smaller. There is a greater distance between the magnets in Pair 1 than in Pair 2. So, the magnitude of the magnetic force is smaller in Pair 1 than in Pair 2.

Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the magnitude of a magnetic force between two magnets by changing the distance between them. The magnitude of the magnetic force is smaller when there is a greater distance between the magnets. Distance affects the magnitude of the magnetic force. When there is a greater distance between magnets, the magnitude of the magnetic force between them is smaller. There is a greater distance between the magnets in Pair 1 than in Pair 2. So, the magnitude of the magnetic force is smaller in Pair 1 than in Pair 2.

The magnitude of the magnetic force is smaller in Pair 1.

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Is Danio rerio made up of many cells?

natural science

In the past, scientists classified living organisms into two groups: plants and animals. Over the past 300 years, scientists have discovered many more types of organisms. Today, many scientists classify organisms into six broad groups, called kingdoms. Organisms in each kingdom have specific traits. The table below shows some traits used to describe each kingdom. | Bacteria | Archaea | Protists | Fungi | Animals | Plants How many cells do they have? | one | one | one or many | one or many | many | many Do their cells have a nucleus? | no | no | yes | yes | yes | yes Can their cells make food? | some species can | some species can | some species can | no | no | yes

Danio rerio is an animal. Animals are made up of many cells.

In the past, scientists classified living organisms into two groups: plants and animals. Over the past 300 years, scientists have discovered many more types of organisms. Today, many scientists classify organisms into six broad groups, called kingdoms. Organisms in each kingdom have specific traits. The table below shows some traits used to describe each kingdom. | Bacteria | Archaea | Protists | Fungi | Animals | Plants How many cells do they have? | one | one | one or many | one or many | many | many Do their cells have a nucleus? | no | no | yes | yes | yes | yes Can their cells make food? | some species can | some species can | some species can | no | no | yes Danio rerio is an animal. Animals are made up of many cells.

yes

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Which property do these two objects have in common?

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Different objects can have the same properties. You can use these properties to put objects into groups.

Look at each object. For each object, decide if it has that property. A bendable object can be bent without breaking. Both objects are bendable. Yellow is a color. This color is yellow. The trampoline is not yellow. The property that both objects have in common is bendable.

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Different objects can have the same properties. You can use these properties to put objects into groups. Look at each object. For each object, decide if it has that property. A bendable object can be bent without breaking. Both objects are bendable. Yellow is a color. This color is yellow. The trampoline is not yellow. The property that both objects have in common is bendable.

bendable

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Which property do these two objects have in common?

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Different objects can have the same properties. You can use these properties to put objects into groups.

Look at each object. For each object, decide if it has that property. Potato chips have a salty taste. Both objects are salty. A shiny object reflects a lot of light. Neither of the objects are shiny. The property that both objects have in common is salty.

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Different objects can have the same properties. You can use these properties to put objects into groups. Look at each object. For each object, decide if it has that property. Potato chips have a salty taste. Both objects are salty. A shiny object reflects a lot of light. Neither of the objects are shiny. The property that both objects have in common is salty.

salty

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