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What is the probability that a rabbit produced by this cross will have black fur?
[ "4/4", "1/4", "3/4", "0/4", "2/4" ]
0
In a group of rabbits, some individuals have black fur and others have brown fur. In this group, the gene for the fur color trait has two alleles. The allele for brown fur (f) is recessive to the allele for black fur (F). This Punnett square shows a cross between two rabbits.
closed choice
grade8
natural science
biology
Genes to traits
Use Punnett squares to calculate probabilities of offspring types
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. In a Punnett square, each box represents a different outcome, or result. Each of the four outcomes is equally likely to happen. Each box represents one way the parents' alleles can combine to form an offspring's genotype. Because there are four boxes in the Punnett square, there are four possible outcomes. An event is a set of one or more outcomes. The probability of an event is a measure of how likely the event is to happen. This probability is a number between 0 and 1, and it can be written as a fraction: probability of an event = number of ways the event can happen / number of equally likely outcomes You can use a Punnett square to calculate the probability that a cross will produce certain offspring. For example, the Punnett square below has two boxes with the genotype Ff. It has one box with the genotype FF and one box with the genotype ff. This means there are two ways the parents' alleles can combine to form Ff. There is one way they can combine to form FF and one way they can combine to form ff. | F | f F | FF | Ff f | Ff | ff Consider an event in which this cross produces an offspring with the genotype ff. The probability of this event is given by the following fraction: number of ways the event can happen / number of equally likely outcomes = number of boxes with the genotype ff / total number of boxes = 1 / 4.
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Which is a complex sentence?
[ "Despite their large size, grizzly bears can run at speeds of up to thirty miles per hour.", "In the early morning, I drank tea by a spice stall as the Turkish bazaar came to life." ]
1
closed choice
grade5
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple, compound, or complex?
A clause is a group of words that contains both a subject and a predicate. An independent clause is a complete thought. It can stand alone as a sentence. A dependent clause is not a complete thought. It cannot stand alone as a sentence. the oranges on our tree are ripe The clause can stand alone. It is independent. after we pick up Kevin from work The clause cannot stand alone. It is dependent. A simple sentence is made up of a single independent clause. Ben and I spent all day relaxing by the pool. Some simple sentences have introductory phrases, but the introductory phrase is part of the predicate. In the winter, Ben usually wears his heavy coat. Ben usually wears his heavy coat in the winter. A compound sentence is made up of two independent clauses joined by a coordinating conjunction such as and, but, or, or so. We saw a flash of lightning, and seconds later we heard the rumble of thunder. A complex sentence is made up of an independent clause and a dependent clause. The dependent clause usually begins with a subordinating conjunction such as after, although, as, because, before, if, since, unless, until, when, or while. If she ever gets the chance, Terri would love to visit the Egyptian pyramids.
The first sentence is the complex sentence. It is made up of an independent clause and a dependent clause. The dependent clause begins with the subordinating conjunction as. In the early morning, I drank tea by a spice stall as the Turkish bazaar came to life.
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Which tense does the sentence use? We will miss you very much!
[ "past tense", "future tense", "present tense" ]
1
closed choice
grade2
language science
verbs
Verb tense
Is the sentence in the past, present, or future tense?
Present tense verbs tell you about something that is happening now. Most present-tense verbs are regular. They have no ending, or they end in -s or -es. Two verbs are irregular in the present tense, to be and to have. You must remember their forms. Past tense verbs tell you about something that has already happened. Most past-tense verbs are regular. They end in -ed. Some verbs are irregular in the past tense. You must remember their past-tense forms. Future tense verbs tell you about something that is going to happen. All future-tense verbs use the word will. Present | Past | Future walk, walks | walked | will walk go, goes | went | will go
The sentence is in future tense. You can tell because it uses will before the main verb, miss. The verb tells you about something that is going to happen.
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Select the vertebrate.
[ "pipevine swallowtail butterfly", "ladybug", "great blue heron", "crown jellyfish" ]
2
Hint: Mammals, birds, fish, reptiles, and amphibians are vertebrates.
closed choice
grade5
natural science
biology
Classification
Identify vertebrates and invertebrates
Vertebrates and invertebrates are both groups of animals. A vertebrate has a backbone. The backbone is made of many bones in an animal's back. A vertebrate's backbone helps connect the different parts of its body. In the drawings below, each vertebrate's backbone is colored orange. An invertebrate does not have a backbone. In fact, invertebrates do not have any bones! Some invertebrates have an outer cover on their body called an exoskeleton. Other invertebrates have a soft body.
A ladybug is an insect. Like other insects, a ladybug is an invertebrate. It does not have a backbone. It has an exoskeleton. A great blue heron is a bird. Like other birds, a great blue heron is a vertebrate. It has a backbone. Like other jellyfishes, a crown jellyfish is an invertebrate. It does not have a backbone. It has a soft body. A pipevine swallowtail butterfly is an insect. Like other insects, a pipevine swallowtail butterfly is an invertebrate. It does not have a backbone. It has an exoskeleton.
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Based on this information, what is Jinx's genotype for the agouti fur gene?
[ "aa", "not having agouti fur" ]
0
This passage describes the agouti fur trait in cats: In a group of cats, some individuals have agouti fur and others do not. In this group, the gene for the agouti fur trait has two alleles. The allele A is for having agouti fur, and the allele a is for not having agouti fur. Jinx, a cat from this group, does not have agouti fur. Jinx has two alleles for not having agouti fur.
closed choice
grade8
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait.
An organism's genotype for a gene is its combination of alleles for that gene. Jinx has two alleles for not having agouti fur (a). So, Jinx's genotype for the agouti fur gene is aa.
Which of these states is farthest west?
[ "Indiana", "Missouri", "Mississippi", "Colorado" ]
3
closed choice
grade3
social science
geography
Geography
Read a map: cardinal directions
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. Colorado is farthest west.
During this time, thermal energy was transferred from () to ().
[ "the surroundings . . . each aquarium", "each aquarium . . . the surroundings" ]
1
Two identical aquariums were next to an open window. One aquarium had a plastic cover on it, and the other was uncovered. This table shows how the temperature of each aquarium changed over 1.5hours.
closed choice
grade7
natural science
physics
Thermal energy
Compare thermal energy transfers
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.
Which ocean is highlighted?
[ "the Atlantic Ocean", "the Pacific Ocean", "the Indian Ocean", "the Southern Ocean" ]
1
closed choice
grade6
social science
geography
Physical Geography
Oceans and continents
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.
Which better describes the Monongahela National Forest ecosystem?
[ "It has warm, dry summers. It also has many different types of trees.", "It has warm, wet summers. It also has only a few types of trees." ]
1
Figure: Monongahela National Forest. The Monongahela National Forest is a temperate deciduous forest ecosystem in eastern West Virginia.
closed choice
grade4
natural science
biology
Ecosystems
Describe ecosystems
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 warm, wet summers. It also has only a few types of trees.
Select the reptile below.
[ "leaf-tailed gecko", "Banggai cardinalfish", "red-eyed tree frog", "clownfish" ]
0
Reptiles have scaly, waterproof skin. Most reptiles live on land. Reptiles are cold-blooded. The body temperature of cold-blooded animals depends on their environment. A box turtle is an example of a reptile.
closed choice
grade4
natural science
biology
Classification
Identify mammals, birds, fish, reptiles, and amphibians
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 leaf-tailed gecko is a reptile. It has scaly, waterproof skin. Many geckos have special pads on their toes. The pads help them climb up plants and rocks. 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 brown anemone surrounding the clownfish. A red-eyed tree frog is an amphibian. It has moist skin and begins its life in water. A red-eyed tree frog has sticky pads on its toes. The sticky pads help the red-eyed tree frog hold on to leaves. A Banggai cardinalfish is a fish. It lives underwater. It has fins, not limbs. Cardinalfish often live near coral reefs. They are nocturnal, which means that they are active mostly at night.
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What is the mass of an elephant?
[ "6,090 kilograms", "6,090 grams" ]
0
Select the better estimate.
closed choice
grade5
natural science
units-and-measurement
Units and measurement
Choose metric units of mass
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Mass is a measurement of how much matter something contains. There are many different units of mass. When you are using metric units, mass may be written with units of grams or kilograms. There are 1,000 grams in 1 kilogram. So, 1 gram is much less than 1 kilogram. A paper clip has a mass of about 1 gram, while a textbook has a mass of about 1 kilogram.
The better estimate for the mass of an elephant is 6,090 kilograms. 6,090 grams is too light.
Select the amphibian below.
[ "red-eyed tree frog", "robin" ]
0
Amphibians have moist skin and begin their lives in water. A green frog is an example of an amphibian.
closed choice
grade2
natural science
biology
Classification
Identify mammals, birds, fish, reptiles, and amphibians
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 robin is a bird. It has feathers, two wings, and a beak. A red-eyed tree frog is an amphibian. It has moist skin and begins its life in water.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnitude of the magnetic force is smaller in Pair 2.", "The magnitude of the magnetic force is smaller in Pair 1.", "The magnitude of the magnetic force is the same in both pairs." ]
1
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade7
natural science
physics
Velocity, acceleration, and forces
Compare magnitudes of magnetic forces
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.
Which continent is highlighted?
[ "Australia", "South America", "Antarctica", "North America" ]
3
closed choice
grade4
social science
geography
Oceans and continents
Identify oceans and continents
A continent is one of the major land masses on the earth. Most people say there are seven continents.
This continent is North America.
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What is the volume of a kiddie pool?
[ "275 gallons", "275 cups", "275 fluid ounces" ]
0
Select the best estimate.
closed choice
grade4
natural science
units-and-measurement
Units and measurement
Choose customary units of volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Volume is a measurement of how much space something takes up. There are many different units of volume. When you are using customary units, volume may be written in units of fluid ounces, cups, or gallons. As the diagram shows, there are 8 fluid ounces in 1 cup and 16 cups in 1 gallon. So, 1 fluid ounce is less than 1 cup and much less than 1 gallon. A glass of milk has a volume of about 8 fluid ounces, or 1 cup. A jug of milk has a volume of 1 gallon.
The best estimate for the volume of a kiddie pool is 275 gallons. 275 fluid ounces and 275 cups are both too little.
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Look at the word. Does it have a closed syllable or an open syllable? men
[ "closed", "open" ]
0
closed choice
grade2
language science
word-study
Short and long vowels
Is the syllable open or closed?
Words are made up of syllables. Two kinds of syllables are closed and open. A closed syllable has one vowel and ends with a consonant. It usually has a short vowel sound. desk: short e kit / ten: short i / short e An open syllable ends with one vowel. It usually has a long vowel sound. go: long o he / ro: long e / long o Some open syllables end with y. The y makes a long e sound or a long i sound. sky: long i ba / by: long a / long e
The word men ends with a consonant and has a short vowel sound. So, it has a closed syllable.
What is the capital of Idaho?
[ "Salt Lake City", "Topeka", "Boise", "Denver" ]
2
closed choice
grade4
social science
geography
State capitals
Identify state capitals of the West
Boise is the capital of Idaho.
Is gneiss a mineral or a rock?
[ "mineral", "rock" ]
1
Gneiss has the following properties: not a pure substance not made by organisms found in nature made of light and dark mineral grains no fixed crystal structure solid
closed choice
grade8
natural science
earth-science
Rocks and minerals
Identify rocks and minerals
Minerals are the building blocks of rocks. A rock can be made of one or more minerals. Minerals and rocks have the following properties: Property | Mineral | Rock It is a solid. | Yes | Yes It is formed in nature. | Yes | Yes It is not made by organisms. | Yes | Yes It is a pure substance. | Yes | No It has a fixed crystal structure. | Yes | No You can use these properties to tell whether a substance is a mineral, a rock, or neither. Look closely at the last three properties: Minerals and rocks are 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 or rocks. Humans are organisms too. So, substances that humans make by hand or in factories are not minerals or rocks. A mineral is a pure substance, but a rock is not. A pure substance is made of only one type of matter. Minerals are pure substances, but rocks are not. Instead, all rocks are mixtures. A mineral has a fixed crystal structure, but a rock does not. 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 and molecules in different pieces of the same type of mineral are always arranged the same way. However, rocks do not have a fixed crystal structure. So, the arrangement of atoms or molecules in different pieces of the same type of rock may be different!
The properties of gneiss match the properties of a rock. So, gneiss is a rock.
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Based on this information, what is Oliver's genotype for the agouti fur gene?
[ "AA", "having agouti fur" ]
0
This passage describes the agouti fur trait in cats: In a group of cats, some individuals have agouti fur and others do not. In this group, the gene for the agouti fur trait has two alleles. The allele A is for having agouti fur, and the allele a is for not having agouti fur. Oliver, a cat from this group, has agouti fur. Oliver has two alleles for having agouti fur.
closed choice
grade8
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait.
An organism's genotype for a gene is its combination of alleles for that gene. Oliver has two alleles for having agouti fur (A). So, Oliver's genotype for the agouti fur gene is AA.
Is the following statement about our solar system true or false? 75% of the planets are made mainly of rock.
[ "true", "false" ]
1
Use the data to answer the question below.
true-or false
grade7
natural science
earth-science
Astronomy
Analyze data to compare properties of planets
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 four out of the eight planets are made mainly of rock. So, one-half, or 50%, of the planets are made mainly of rock.
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What is the source of the allusion in the sentence below? Yesterday's tennis match was a classic David and Goliath story, with Stanley playing against his former team captain, Richard.
[ "the Bible", "a poem" ]
0
closed choice
grade7
language science
figurative-language
Literary devices
Recall the source of an allusion
An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words. "I'd better get home before I turn into a pumpkin!" Lila remarked. Here, Lila alludes to the fairy tale "Cinderella," in which Cinderella must leave the ball before the coach that brought her transforms into a pumpkin. The allusion shows that Lila must depart immediately.
The source of the allusion David and Goliath is the Bible. In the Bible, a young man named David slays Goliath, a giant and champion warrior, using nothing more than a sling and a stone. The allusion David and Goliath means involving unequal rivals.
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What do these two changes have in common? a piece of apple turning brown bleaching clothes
[ "Both are chemical changes.", "Both are only physical changes.", "Both are caused by cooling.", "Both are caused by heating." ]
0
closed choice
grade7
natural science
chemistry
Chemical reactions
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form different molecules. The types of molecules in matter before and after a chemical change are always different. Some chemical changes are caused by heating or cooling. For example, burning a piece of paper is a chemical change caused by heating. As paper burns, paper molecules react with oxygen molecules in the air. This reaction breaks the chemical bonds in the molecules. The atoms then link together in a different way to form different molecules. For example, carbon dioxide molecules are formed when paper burns. In a physical change, chemical bonds do not break. The types of molecules in matter before and after a physical change are always the same. A change of state is a type of physical change. Changes of state can be caused by heating or cooling. For example, water vaporizing is a physical change that can be caused by heating. Liquid water and water vapor are made of the same type of matter: water. The law of conservation of mass says that all physical and chemical changes conserve mass. Conserve means to keep the same. So, the total mass before a physical or chemical change is equal to the total mass after the change.
Step 1: Think about each change. A piece of apple turning brown is a chemical change. The apple reacts with oxygen in the air and turns into a different type of matter. If you scrape off the brown layer of the apple, the inside is still white. The inside hasn't touched the air. So the chemical change didn't happen to that part of the apple. Bleaching clothes is a chemical change. The bleach reacts with dark stains on the clothes. The reaction changes the stains into different types of matter that wash away easily. Step 2: Look at each answer choice. Both are only physical changes. Both changes are chemical changes. They are not physical changes. Both are chemical changes. Both changes are chemical changes. The type of matter before and after each change is different. Both are caused by heating. Neither change is caused by heating. Both are caused by cooling. Neither change is caused by cooling.
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Suppose Jayden decides to take a trip to Nevada. Which result would be a cost?
[ "Jayden will enjoy his trip to Nevada more than he would have enjoyed a trip to Connecticut.", "Jayden will spend more money. Plane tickets for Jayden to get to Nevada are more expensive than tickets to Connecticut." ]
1
Jayden is deciding whether to take a trip to Nevada or Connecticut. He wants to enjoy his trip. But he is also trying to save money.
closed choice
grade4
social science
economics
Basic economic principles
Costs and benefits
Before you decide to do something, it is often helpful to list costs and benefits. Costs are what you give up or spend when you decide to do something. Costs involve giving up things that you want or need. Benefits are what you gain or save when you decide to do something. Benefits involve gaining something that you want or need.
This result is a cost. It involves giving up or spending something that Jayden wants or needs: Jayden will spend more money. Plane tickets for Jayden to get to Nevada are more expensive than tickets to Connecticut.
Which better describes the Kibale National Forest ecosystem?
[ "It has year-round rain. It also has many different types of organisms.", "It has cold winters. It also has soil that is rich in nutrients." ]
0
Figure: Kibale National Forest. Kibale National Forest is a tropical rain forest ecosystem in Uganda, a country in eastern Africa.
closed choice
grade3
natural science
biology
Ecosystems
Describe ecosystems
An ecosystem is formed when living and nonliving things interact in an environment. There are many types of ecosystems. Here are some ways in which ecosystems can differ from each other: the pattern of weather, or climate the type of soil or water the organisms that live there
A tropical rain forest is a type of ecosystem. Tropical rain forests have the following features: year-round rain and warm temperatures, soil that is poor in nutrients, and many different types of organisms. So, Kibale National Forest has year-round rain. It also has many different types of organisms.
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How long is a hammer?
[ "24 centimeters", "24 meters", "24 millimeters", "24 kilometers" ]
0
Select the best estimate.
closed choice
grade7
natural science
units-and-measurement
Units and measurement
Choose metric units of distance, mass, and volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. When you are using metric units, length can be written with units of millimeters, centimeters, meters, or kilometers. One meter contains 100 centimeters or 1,000 millimeters. So, 1 meter is larger than 1 centimeter, and 1 centimeter is larger than 1 millimeter. The tip of the pencil shown here is only 1 millimeter wide, but the pencil is about 16 centimeters long. A red fox is about 1 meter long. The Sydney Harbour Bridge in Australia is about 1,000 meters, or 1 kilometer, in length.
The best estimate for the length of a hammer is 24 centimeters. 24 millimeters is too short. 24 meters and 24 kilometers are too long.
Select the amphibian below.
[ "golden frog", "bison" ]
0
Amphibians have moist skin and begin their lives in water. A red-eyed tree frog is an example of an amphibian.
closed choice
grade2
natural science
biology
Classification
Identify mammals, birds, fish, reptiles, and amphibians
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 golden frog is an amphibian. It has moist skin and begins its life in water. A bison is a mammal. It has fur and feeds its young milk.
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Assume all other forces on Kylie are balanced. Which statement describes the forces on Kylie?
[ "The forces are balanced, so there is no net force on Kylie.", "The forces are unbalanced, so there is a net force on Kylie." ]
1
Kylie is sitting on a roller coaster cart as it reaches the bottom of a big loop. Earth's gravity is pulling down on Kylie with a force of 600N. The seat of the cart is pushing up on Kylie with a force of 1,200N.
closed choice
grade6
natural science
physics
Velocity, acceleration, and forces
Balanced and unbalanced forces
A force is a push or a pull that acts on an object. Every force has a direction and a magnitude, or strength. If two forces act on an object in opposite directions, the forces are called opposing forces. When opposing forces have the same magnitude, they are balanced. If all the forces on an object are balanced, there is no net force on the object. When opposing forces have different magnitudes, the forces are unbalanced. If any forces on an object are unbalanced, there is a net force on the object.
To determine if there is a net force on Kylie, look at the forces: Earth's gravity is pulling Kylie down with a force of 600 N. The seat of the cart is pushing Kylie up with a force of 1,200 N. The forces are in opposite directions, and the forces have different magnitudes: 600 N and 1,200 N. This means that the forces are unbalanced, so there is a net force on Kylie.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnetic force is weaker in Pair 2.", "The strength of the magnetic force is the same in both pairs.", "The magnetic force is weaker in Pair 1." ]
2
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade3
natural science
physics
Magnets
Compare strengths of magnetic forces
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.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The strength of the magnetic force is the same in both pairs.", "The magnetic force is weaker in Pair 1.", "The magnetic force is weaker in Pair 2." ]
0
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade4
natural science
physics
Magnets
Compare strengths of magnetic forces
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.
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Select the one substance that is not a mineral.
[ "Graphite is formed in nature. It is a pure substance.", "A brick is made by humans. It is not a pure substance.", "Quartz is formed in nature. It is a pure substance." ]
1
closed choice
grade4
natural science
earth-science
Rocks and minerals
Identify minerals using properties
Minerals are the building blocks of rocks. A rock can be made of one or more minerals. Minerals and rocks have the following properties: Property | Mineral | Rock It is a solid. | Yes | Yes It is formed in nature. | Yes | Yes It is not made by organisms. | Yes | Yes It is a pure substance. | Yes | No It has a fixed crystal structure. | Yes | No You can use these properties to tell whether a substance is a mineral, a rock, or neither. Look closely at the last three properties: Minerals and rocks are 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 or rocks. Humans are organisms too. So, substances that humans make by hand or in factories are not minerals or rocks. A mineral is a pure substance, but a rock is not. A pure substance is made of only one type of matter. Minerals are pure substances, but rocks are not. Instead, all rocks are mixtures. A mineral has a fixed crystal structure, but a rock does not. 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 and molecules in different pieces of the same type of mineral are always arranged the same way. However, rocks do not have a fixed crystal structure. So, the arrangement of atoms or molecules in different pieces of the same type of rock may be different!
Compare the properties of each substance to the properties of minerals. Select the substance whose properties do not match those of minerals. A brick is made by humans. But minerals are not made by living things. A brick is not a pure substance. But all minerals are pure substances. So, a brick is not a mineral. Quartz is a mineral. Graphite is a mineral.
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How long is a bike path?
[ "3 centimeters", "3 kilometers" ]
1
Select the better estimate.
closed choice
grade3
natural science
units-and-measurement
Units and measurement
Choose metric units of distance
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Imagine being told that a pencil is 16 long. You might be thinking, 16 what? Is the pencil 16 centimeters long? 16 meters? 16 kilometers? The number 16 on its own does not give you much information about the length of the pencil. That is because the units are missing. Now look at the drawing of the pencil and the ruler. The ruler shows that the units are centimeters. So, the length of the pencil is 16 centimeters. There are 100 centimeters in 1 meter. So, 1 centimeter is much shorter than 1 meter. There are 1,000 meters in 1 kilometer. So, 1 meter is much shorter than 1 kilometer.
The better estimate for the length of a bike path is 3 kilometers. 3 centimeters is too short.
What is the capital of Alaska?
[ "Tallahassee", "Fairbanks", "Anchorage", "Juneau" ]
3
closed choice
grade4
social science
geography
State capitals
Identify state capitals of the West
Juneau is the capital of Alaska.
What is the capital of Arizona?
[ "Juneau", "Phoenix", "Reno", "Tucson" ]
1
closed choice
grade3
social science
geography
State capitals
Identify state capitals of the West
Phoenix is the capital of Arizona.
What is the capital of Colorado?
[ "Boulder", "Denver", "Cheyenne", "Boise" ]
1
closed choice
grade4
social science
geography
State capitals
Identify state capitals of the West
Denver is the capital of Colorado.
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Compare the motion of three speedboats. Which speedboat was moving at the lowest speed?
[ "a speedboat that moved 890kilometers west in 10hours", "a speedboat that moved 880kilometers north in 10hours", "a speedboat that moved 360kilometers west in 10hours" ]
2
closed choice
grade3
natural science
physics
Force and motion
Compare the speeds of moving objects
An object's speed tells you how fast the object is moving. Speed depends on both distance and time. Distance tells you how far the object has moved. One unit used to measure distance is the kilometer. Time tells you how long the object has spent moving. One unit used to measure time is the hour. Think about objects moving for the same amount of time. The object that is moving the slowest will go the shortest distance in that time. It is moving at the lowest speed.
Look at the distance each speedboat moved and the time it took to move that distance. The direction each speedboat moved does not affect its speed. Notice that each speedboat moved for 10 hours. The speedboat that moved 360 kilometers moved the shortest distance in that time. So, that speedboat must have moved at the lowest speed.
Which property do these three objects have in common?
[ "bouncy", "fuzzy", "sweet" ]
2
Select the best answer.
closed choice
grade4
natural science
physics
Materials
Compare properties of objects
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. Sugar has a sweet taste. All three objects are sweet. A fuzzy object is covered in soft hair. The chocolate bar and the candy sprinkles are not fuzzy. A bouncy object will bounce back from the floor if you drop it. The chocolate bar is not bouncy. The property that all three objects have in common is sweet.
Is malachite a mineral?
[ "yes", "no" ]
0
Malachite has the following properties: pure substance solid naturally occurring fixed crystal structure not made by living things
yes or no
grade6
natural science
earth-science
Rocks and minerals
Identify rocks and minerals
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.
Malachite has all the properties of a mineral. So, malachite is a mineral.
Is the following statement about our solar system true or false? 75% of the planets are made mainly of rock.
[ "false", "true" ]
0
Use the data to answer the question below.
true-or false
grade6
natural science
earth-science
Astronomy
Analyze data to compare properties of planets
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 four out of the eight planets are made mainly of rock. So, one-half, or 50%, of the planets are made mainly of rock.
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Is the following trait inherited or acquired? Regan has naturally dark skin.
[ "acquired", "inherited" ]
1
closed choice
grade5
natural science
biology
Traits and heredity
Identify inherited and acquired traits
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Children do not inherit their parents' acquired traits.
Humans do not choose their skin color. Babies get their skin color from their parents. So, Regan's skin color is an inherited trait.
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How long is a leather belt?
[ "75 centimeters", "75 meters" ]
0
Select the better estimate.
closed choice
grade2
natural science
units-and-measurement
Units and measurement
Choose metric units of distance
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Imagine being told that a pencil is 16 long. You might be thinking, 16 what? Is the pencil 16 centimeters long? 16 meters? 16 kilometers? The number 16 on its own does not give you much information about the length of the pencil. That is because the units are missing. Now look at the drawing of the pencil and the ruler. The ruler shows that the units are centimeters. So, the length of the pencil is 16 centimeters. There are 100 centimeters in 1 meter. So, 1 centimeter is much shorter than 1 meter. There are 1,000 meters in 1 kilometer. So, 1 meter is much shorter than 1 kilometer.
The better estimate for the length of a leather belt is 75 centimeters. 75 meters is too long.
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What do these two changes have in common? melting glass cooking an egg
[ "Both are only physical changes.", "Both are caused by heating.", "Both are chemical changes.", "Both are caused by cooling." ]
1
closed choice
grade8
natural science
chemistry
Chemical reactions
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form different molecules. The types of molecules in matter before and after a chemical change are always different. Some chemical changes are caused by heating or cooling. For example, burning a piece of paper is a chemical change caused by heating. As paper burns, paper molecules react with oxygen molecules in the air. This reaction breaks the chemical bonds in the molecules. The atoms then link together in a different way to form different molecules. For example, carbon dioxide molecules are formed when paper burns. In a physical change, chemical bonds do not break. The types of molecules in matter before and after a physical change are always the same. A change of state is a type of physical change. Changes of state can be caused by heating or cooling. For example, water vaporizing is a physical change that can be caused by heating. Liquid water and water vapor are made of the same type of matter: water. The law of conservation of mass says that all physical and chemical changes conserve mass. Conserve means to keep the same. So, the total mass before a physical or chemical change is equal to the total mass after the change.
Step 1: Think about each change. Melting glass is a change of state. So, it is a physical change. The glass changes from solid to liquid. But a different type of matter is not formed. Cooking an egg is a chemical change. The heat causes the matter in the egg to change. Cooked egg and raw egg are different types of matter. Step 2: Look at each answer choice. Both are only physical changes. Melting glass is a physical change. But cooking an egg is not. Both are chemical changes. Cooking an egg is a chemical change. But melting glass is not. Both are caused by heating. Both changes are caused by heating. Both are caused by cooling. Neither change is caused by cooling.
Which property do these three objects have in common?
[ "opaque", "stretchy", "fragile" ]
0
Select the best answer.
closed choice
grade3
natural science
physics
Materials
Compare properties of objects
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.
Look at each object. For each object, decide if it has that property. A fragile object will break into pieces if you drop it. The steel beam and the towel are not fragile. A stretchy object gets longer when you pull on it. The steel beam and the popcorn are not stretchy. An opaque object does not let light through. All three objects are opaque. The property that all three objects have in common is opaque.
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How long is a leather belt?
[ "70 kilometers", "70 meters", "70 centimeters" ]
2
Select the best estimate.
closed choice
grade4
natural science
units-and-measurement
Units and measurement
Choose metric units of distance
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. When you are using metric units, length can be written with units of millimeters, centimeters, meters, or kilometers. One meter contains 100 centimeters or 1,000 millimeters. So, 1 meter is larger than 1 centimeter, and 1 centimeter is larger than 1 millimeter. The tip of the pencil shown here is only 1 millimeter wide, but the pencil is about 16 centimeters long. A red fox is about 1 meter long. The Sydney Harbour Bridge in Australia is about 1,000 meters, or 1 kilometer, in length.
The best estimate for the length of a leather belt is 70 centimeters. 70 meters and 70 kilometers are both too long.
Does this passage describe the weather or the climate?
[ "climate", "weather" ]
0
Figure: Uganda. Uganda is an African country near the equator. It has large forests which are humid during April and May each year. Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.
closed choice
grade6
natural science
earth-science
Weather and climate
Weather and climate around the world
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. Uganda is an African country near the equator. It has large forests which are humid during April and May each year. The underlined part of the passage tells you about the usual pattern of humidity in Uganda. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.
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What is the mass of a goat?
[ "75 ounces", "75 pounds", "75 tons" ]
1
Select the best estimate.
closed choice
grade4
natural science
units-and-measurement
Units and measurement
Choose customary units of mass
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Mass is a measurement of how much matter something contains. There are many different units of mass. When you are using customary units, mass may be written with units of ounces, pounds, or tons. There are 16 ounces in 1 pound and 2,000 pounds in 1 ton. So, 1 ounce is less than 1 pound and much less than 1 ton. A slice of bread has a mass of about 1 ounce, while a can of beans has a mass of about 1 pound. A small car has a mass of about 1 ton.
The best estimate for the mass of a goat is 75 pounds. 75 ounces is too light and 75 tons is too heavy.
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Which text uses the word unique in its traditional sense?
[ "The Supreme Court case Miranda v. Arizona, which led to the institution of the Miranda warning, was quite unique in that it had significant implications for law enforcement. Only a handful of Supreme Court decisions have had such an impact on daily police procedure.", "The Miranda warning, the reading of rights given to a suspect by police prior to questioning, is not unique to the United States; a number of other countries have equivalent rights, including Australia, South Africa, Switzerland, Thailand, and Kazakhstan." ]
1
closed choice
grade9
language science
writing-strategies
Word usage and nuance
Explore words with new or contested usages
Words change in meaning when speakers begin using them in new ways. For example, the word peruse once only meant to examine in detail, but it's now also commonly used to mean to look through in a casual manner. When a word changes in meaning, its correct usage is often debated. Although a newer sense of the word may be more commonly used, many people consider a word's traditional definition to be the correct usage. Being able to distinguish the different uses of a word can help you use it appropriately for different audiences. Britney perused her notes, carefully preparing for her exam. The traditional usage above is considered more standard. David perused the magazine, absentmindedly flipping through the pages. The nontraditional usage above is now commonly used, but traditional style guides generally advise against it.
The second text uses unique in its traditional sense: being the only one of its kind. The Miranda warning, the reading of rights given to a suspect by police prior to questioning, is not unique to the United States; a number of other countries have equivalent rights, including Australia, South Africa, Switzerland, Thailand, and Kazakhstan. The first text uses unique in its nontraditional sense: interesting or unusual. Miranda v. Arizona was one of a few Supreme Court cases to have implications for law enforcement, so it was not one of a kind in that respect. It may be helpful to remember that if unique is modified by an adverb—as in most unique, very unique, or quite unique—it is probably being used nontraditionally. The Supreme Court case Miranda v. Arizona, which led to the institution of the Miranda warning, was quite unique in that it had significant implications for law enforcement. Only a handful of Supreme Court decisions have had such an impact on daily police procedure. Most style guides recommend to use the traditional sense of the word unique because it is considered more standard.
Which solution has a higher concentration of yellow particles?
[ "Solution A", "Solution B", "neither; their concentrations are the same" ]
1
The diagram below is a model of two solutions. Each yellow ball represents one particle of solute.
closed choice
grade8
natural science
chemistry
Solutions
Compare concentrations of solutions
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 yellow particles represent the solute. To figure out which solution has a higher concentration of yellow particles, look at both the number of yellow particles and the volume of the solvent in each container. Use the concentration formula to find the number of yellow particles per milliliter. Solution B has more yellow particles per milliliter. So, Solution B has a higher concentration of yellow particles.
Which of these states is farthest west?
[ "Georgia", "Mississippi", "Maine", "Vermont" ]
1
closed choice
grade2
social science
geography
Geography
Read a map: cardinal directions
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. Mississippi is farthest west.
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Complete the sentence so that it uses personification. The midday sun () the hikers.
[ "glared at", "warmed" ]
0
closed choice
grade10
language science
writing-strategies
Creative techniques
Use personification
Personification is giving human characteristics to nonhuman things. It is a figure of speech that can be used to make writing more interesting or to emphasize a point. The trees danced in the wind. The word danced describes the trees as if they were people. Unlike people, however, trees can't actually dance. Instead, the personification suggests that the trees are moving.
Complete the sentence with the phrase glared at. It describes the sun as if it were a person giving an angry look.
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Which of the following contains a vague pronoun reference?
[ "Bob had to stay home with his brother because he wasn't feeling well.", "Bob's brother wasn't feeling well, so Bob had to stay home with him." ]
0
closed choice
grade11
language science
writing-strategies
Pronouns
Identify vague pronoun references
When writing, make sure to avoid vague pronoun references. A vague pronoun reference occurs when a pronoun could refer to more than one possible antecedent. When Lisa and Kim finally landed, she breathed a sigh of relief. The pronoun she could refer to either Lisa or Kim, so the meaning of the sentence is unclear. Vague pronoun references can be corrected in one of two ways: 1. Replace the pronoun with its correct antecedent: When Lisa and Kim finally landed, Lisa breathed a sigh of relief. 2. Rewrite the sentence: Lisa breathed a sigh of relief when she and Kim finally landed. A vague pronoun reference also occurs when they, them, their, theirs, it, or its is used without its antecedent. They say that this nail polish dries in less than five minutes. The pronoun they is used without its antecedent, so the meaning of the sentence is unclear. This problem can be fixed by replacing the pronoun with its missing antecedent. The advertisements say that this nail polish dries in less than five minutes.
The second answer choice contains a vague pronoun reference. The pronoun he could refer to Bob or his brother. Bob had to stay home with his brother because he wasn't feeling well. The first answer choice shows a possible correction for the vague pronoun reference. The text has been rewritten so that the meaning is clear. Bob's brother wasn't feeling well, so Bob had to stay home with him.
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Which tense does the sentence use? Ellie practices the drums in her family's garage.
[ "present tense", "past tense", "future tense" ]
0
closed choice
grade3
language science
verbs
Verb tense
Is the sentence in the past, present, or future tense?
Present tense verbs tell you about something that is happening now. Most present-tense verbs are regular. They have no ending, or they end in -s or -es. Two verbs are irregular in the present tense, to be and to have. You must remember their forms. Past tense verbs tell you about something that has already happened. Most past-tense verbs are regular. They end in -ed. Some verbs are irregular in the past tense. You must remember their past-tense forms. Future tense verbs tell you about something that is going to happen. All future-tense verbs use the word will. Present | Past | Future walk, walks | walked | will walk go, goes | went | will go
The sentence is in present tense. You can tell because it uses a present-tense verb, practices. The verb ends in -s and tells you about something that is true or happening now.
Which solution has a higher concentration of yellow particles?
[ "neither; their concentrations are the same", "Solution B", "Solution A" ]
2
The diagram below is a model of two solutions. Each yellow ball represents one particle of solute.
closed choice
grade7
natural science
chemistry
Solutions
Compare concentrations of solutions
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 yellow particles represent the solute. To figure out which solution has a higher concentration of yellow particles, look at both the number of yellow particles and the volume of the solvent in each container. Use the concentration formula to find the number of yellow particles per milliliter. Solution A has more yellow particles per milliliter. So, Solution A has a higher concentration of yellow particles.
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Suppose Nancy decides to watch the comedy. Which result would be a cost?
[ "Nancy will get to watch the movie that she is more excited about.", "Nancy will give up the chance to watch a movie with her sister." ]
1
Nancy is deciding whether to watch a comedy or an action movie. She would prefer to watch a comedy. But she also wants to watch a movie with her sister. Nancy's sister will only watch an action movie.
closed choice
grade4
social science
economics
Basic economic principles
Costs and benefits
Before you decide to do something, it is often helpful to list costs and benefits. Costs are what you give up or spend when you decide to do something. Costs involve giving up things that you want or need. Benefits are what you gain or save when you decide to do something. Benefits involve gaining something that you want or need.
This result is a cost. It involves giving up or spending something that Nancy wants or needs: Nancy will give up the chance to watch a movie with her sister.
What is the capital of Oregon?
[ "Phoenix", "Sacramento", "Salem", "Frankfort" ]
2
closed choice
grade5
social science
geography
State capitals
Identify the 50 state capitals
Salem is the capital of Oregon.
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Is the following trait inherited or acquired? Camilla plays basketball.
[ "acquired", "inherited" ]
0
Hint: Playing basketball takes practice.
closed choice
grade4
natural science
biology
Traits and heredity
Identify inherited and acquired traits
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Children do not inherit their parents' acquired traits.
People are not born knowing how to play basketball. Instead, some people learn how to play basketball. Playing the sport takes practice. So, playing basketball is an acquired trait.
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Using only these supplies, which question can Haley investigate with an experiment?
[ "Does a cell phone charge more quickly when it is turned on or when it is turned off?", "Does a tablet charge faster with a two-foot-long charging cable or a five-foot-long charging cable?", "Does a cell phone charge faster when plugged into a wall outlet or into a computer?" ]
0
Haley notices that her cell phone charges more quickly sometimes and more slowly other times. She wonders what factors affect how quickly a phone charges. So, she decides to design an experiment. She has the following supplies available: one cell phone a two-foot-long charging cable a five-foot-long charging cable a stopwatch a wall outlet
closed choice
grade8
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
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What is the source of the allusion in the sentence below? Clara told her friends that Farid was a typical Peter Pan type.
[ "a song", "literature" ]
1
closed choice
grade7
language science
figurative-language
Literary devices
Recall the source of an allusion
An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words. "I'd better get home before I turn into a pumpkin!" Lila remarked. Here, Lila alludes to the fairy tale "Cinderella," in which Cinderella must leave the ball before the coach that brought her transforms into a pumpkin. The allusion shows that Lila must depart immediately.
The source of the allusion Peter Pan is literature. In a J. M. Barrie novel, the character Peter Pan retreats to Neverland and refuses to grow up. The allusion Peter Pan means a person who won't take on adult responsibilities.
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Which is harder?
[ "ceramic mug", "cotton apron" ]
0
closed choice
grade2
natural science
physics
Materials
Compare properties of materials
Every object is made of one or more materials. A material is a type of matter. Wood, glass, metal, and plastic are common materials. A material has different properties. A material's properties tell you how it looks, feels, tastes, or smells.
Hard is a property. A hard material keeps its shape when you press on it with your finger. Look at each picture, one at a time. Imagine pushing on the material shown in each picture. Of the choices, the ceramic mug is harder. If you press on a piece of ceramic, it will not change shape.
What is the capital of Oregon?
[ "Portland", "Boston", "Salem", "Minneapolis" ]
2
closed choice
grade5
social science
geography
State capitals
Identify state capitals of the West
Salem is the capital of Oregon.
Which of these states is farthest north?
[ "Oregon", "Kansas", "Mississippi", "Illinois" ]
0
closed choice
grade5
social science
geography
Maps
Read a map: cardinal directions
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. Oregon is farthest north.
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What is the volume of a water balloon?
[ "485 milliliters", "485 liters" ]
0
Select the better estimate.
closed choice
grade4
natural science
units-and-measurement
Units and measurement
Choose metric units of volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Volume is a measurement of how much space something takes up. There are many different units of volume. When you are using metric units, volume may be written in units of milliliters or liters. There are 1,000 milliliters in 1 liter. So, 1 milliliter is much less than 1 liter. A raindrop has a volume of about 20 milliliters, while a large soda bottle has a volume of 2 liters. The flask shown here measures volumes up to 500 milliliters.
The better estimate for the volume of a water balloon is 485 milliliters. 485 liters is too much.
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Which correctly shows the title of a magazine?
[ "Oceans of the Mind", "oceans of the mind" ]
0
closed choice
grade4
language science
capitalization
Formatting
Capitalizing titles
In a title, capitalize the first word, the last word, and every important word in between. The Wind in the Willows James and the Giant Peach These words are not important in titles: Articles, a, an, the Short prepositions, such as at, by, for, in, of, on, to, up Coordinating conjunctions, such as and, but, or
Capitalize the first word, the last word, and every important word in between. The words of and the are not important, so they should not be capitalized. The correct title is Oceans of the Mind.
Which better describes the Kaeng Krachan National Park ecosystem?
[ "It has year-round warm temperatures. It also has many different types of organisms.", "It has cold winters. It also has many different types of organisms." ]
0
Figure: Kaeng Krachan National Park. Kaeng Krachan National Park is a tropical rain forest ecosystem in western Thailand.
closed choice
grade4
natural science
biology
Ecosystems
Describe ecosystems
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 tropical rain forest is a type of ecosystem. Tropical rain forests have the following features: year-round rain and warm temperatures, soil that is poor in nutrients, and many different types of organisms. So, Kaeng Krachan National Park has year-round warm temperatures. It also has many different types of organisms.
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Which correctly shows the title of a TV show?
[ "***You Can't Do That on Television***", "\"You Can't Do That on Television\"" ]
0
closed choice
grade6
language science
punctuation
Formatting
Formatting titles
The title of a book, movie, play, TV show, magazine, or newspaper should be in italics. If you write it by hand, it can be underlined instead. A Midsummer Night's Dream The title of a poem, song, article, or short story should be in quotation marks. "You Are My Sunshine"
A TV show should be in italics. The correct title is **You Can't Do That on Television**.
Which animal's feet are also adapted for swimming?
[ "purple gallinule", "lava gull" ]
1
Black-bellied whistling ducks live near lakes and streams in North America. They find most of their food in shallow water. The feet of the are adapted for swimming. Figure: black-bellied whistling duck.
closed choice
grade3
natural science
biology
Adaptations
Animal adaptations: feet and limbs
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 feet is one example of an adaptation. Animals' feet can be adapted in different ways. For example, webbed feet might help an animal swim. Feet with thick fur might help an animal walk on cold, snowy ground.
Look at the picture of the black-bellied whistling duck. The black-bellied whistling duck has webbed feet. Its feet are adapted for swimming. As it swims, the black-bellied whistling duck uses its webbed feet to push itself through water. Now look at each animal. Figure out which animal has a similar adaptation. The lava gull has webbed feet. Its feet are adapted for swimming. The purple gallinule has long, thin toes on its feet. Its feet are not adapted for swimming. The purple gallinule uses its feet to walk on large leaves floating on the surface of the water.
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Select the animal that does not have a backbone.
[ "leaf-curling spider", "salmon" ]
0
Hint: Insects, spiders, and worms do not have backbones.
closed choice
grade2
natural science
biology
Classification
Identify animals with and without backbones
Some animals have a backbone. The backbone is made of many bones in an animal's back. An animal's backbone helps connect the different parts of its body. In the drawings below, each animal's backbone is colored orange. Other animals do not have a backbone. In fact, these animals don't have any bones! Some animals without backbones have a hard outer cover. Other animals have a soft body.
Like other spiders, a leaf-curling spider does not have a backbone. It has a hard outer cover. A salmon is a fish. Like other fish, a salmon has a backbone.
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Select the one animal that has all of the bird traits listed above.
[ "Chinese alligators live in lakes and streams in eastern China. They lay eggs with shells and live in underground burrows in the winter. Chinese alligators have scaly, waterproof skin.", "Blue-footed boobies live on tropical islands in the Pacific Ocean. They have two wings, feathers, and a beak. Blue-footed boobies lay eggs with pale blue shells. They keep the eggs warm with their large blue feet." ]
1
Birds are a group of animals with similar traits. The following traits can be used to identify birds: They have feathers. They have wings. They have a beak. They make eggs with shells. Observe the animals and read the descriptions.
closed choice
grade5
natural science
biology
Classification
Use evidence to classify mammals, birds, fish, reptiles, and amphibians
Scientists sort animals with similar traits into groups. This is called classification. Classification helps scientists learn about how animals live. How do scientists classify animals? First, they make observations about an animal. Scientists observe the animal's traits, including its body parts and behavior. Then, scientists compare the animal's traits to other animals' traits. Scientists classify animals with similar traits into a group.
To decide if an animal is part of a group, look at the traits of the group. Birds have the following traits: They have feathers. They have wings. They have a beak. They make eggs with shells. Compare each animal's traits to the group's traits. Select the animal with traits similar to the group's traits. A Chinese alligator has the following traits: It has scaly, waterproof skin. It makes eggs with shells. A Chinese alligator does not have all of the traits of a bird. A Chinese alligator is a reptile. A blue-footed booby has the following traits: It has feathers. It has wings. It has a beak. It makes eggs with shells. A blue-footed booby has the traits of a bird. A blue-footed booby is a bird.
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What information supports the conclusion that Pablo acquired this trait?
[ "Pablo's scar is on his left knee. His mother also has a scar on her left knee.", "Pablo's brother has scars on both of his knees.", "Pablo's scar was caused by an accident. He cut his leg when he fell off his skateboard." ]
2
Read the description of a trait. Pablo has a scar on his left knee.
closed choice
grade7
natural science
biology
Genes to traits
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down from biological parents to their offspring through genes. Genes are pieces of hereditary material that contain the instructions that affect inherited traits. Offspring receive their genes, and therefore gain their inherited traits, from their biological parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Parents do not pass acquired traits down to their offspring.
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Choose the poem that uses repetition.
[ "Down, down, down!\nDown to the depths of the sea!\nShe sits at her wheel in the humming town,\nSinging most joyfully.", "The poor old year died hard; for all the earth lay cold\nAnd bare beneath the wintry sky;\nWhile gray clouds scurried madly to the west,\nAnd hid the chill young moon from mortal sight." ]
0
From Matthew Arnold, "The Forsaken Merman" and from Alice Ruth Moore, "New Year's Day"
closed choice
grade4
language science
reading-comprehension
Poetry elements
Identify elements of poetry
Poetry is a special kind of writing. It has many elements that make it different from ordinary writing. Knowing these elements can help you talk about poetry, understand it better, and enjoy it more. A poem rhymes when it has a pattern of words that end in the same sound. End rhyme is when the rhymes appear at the end of a poem's lines. Little Betty Blue, Lost her holiday shoe. —From Mother Goose Internal rhyme is when at least one of the rhyming words appears inside the poem's lines. Sweet dreams of pleasant streams. —From William Blake, "A Cradle Song" Rhythm is the pattern of strong and weak syllables, or stress, in a poem. You can recognize rhythm in a poem by listening to how it sounds. Poems with regular rhythm have a beat, like in music. He watches from his mountain walls, And like a thunderbolt he falls. —From Alfred, Lord Tennyson, "The Eagle" The syllables in bold are strong. We say them with more force than the other syllables. In this poem, every weak syllable is followed by a strong syllable. Each line sounds like da-DUM da-DUM da-DUM da-DUM. To better hear the rhythm, try reading it aloud while clapping on each strong syllable. Free verse is when a poem has neither a regular rhythm nor a rhyme pattern. The old bridge has a wrinkled face. He bends his back For us to go over. —From Hilda Conkling, "The Old Bridge" The syllables in bold are strong. You can see this poem does not have a regular rhythm. It also doesn't have a rhyme pattern. Repetition is when words, phrases, or whole lines are repeated. The dainty flying squirrel In vest of shining white, In coat of silver gray, And vest of shining white. —Adapted from Mary E. Burt, "The Flying Squirrel" Alliteration is when beginning consonant sounds are repeated in words that are close together. Where the wild men watched and waited Wolves in the forest, and bears in the bush. —From Bayard Taylor, "A Night with a Wolf" Onomatopoeia is when language sounds like what it talks about. Sometimes the onomatopoeia uses made-up words: Tlot-tlot! tlot-tlot! Had they heard it? The horse hoofs ringing clear. —From Alfred Noyes, "The Highwayman" Sometimes the onomatopoeia uses real words: Hark! the honey bee is humming. —From Mary Howitt, "The Voice of Spring"
This poem uses repetition. It repeats words, phrases, or lines. Down, down, down! Down to the depths of the sea! Singing most joyfully.
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Complete the statement. Assume that the water balloon's mass did not change. The gravitational potential energy stored between the water balloon and Earth () as the water balloon fell toward Paul.
[ "increased", "stayed the same", "decreased" ]
2
Read the text about an object in motion. Bridgette dropped a water balloon off a balcony. The water balloon fell toward her friend Paul, who was standing below the balcony.
closed choice
grade8
natural science
physics
Kinetic and potential energy
Identify changes in gravitational potential energy
Gravitational potential energy is stored between any two objects. So, for every object on or near Earth, there is gravitational potential energy stored between the object and Earth. The amount of gravitational potential energy stored between an object and Earth depends on the mass of the object. The amount of gravitational potential energy also depends on the distance between the object and the center of Earth. This distance increases when the object moves higher and decreases when the object moves lower. If the distance between an object and the center of Earth changes, the gravitational potential energy stored between the object and Earth will change. The table below shows how this change can happen. When an object's mass stays the same and its distance from the center of Earth... | Gravitational potential energy stored between the object and Earth... increases | increases decreases | decreases stays the same | stays the same
Think about how the distance between the water balloon and the center of Earth changed. Paul was lower than the balcony. As the water balloon fell toward Paul, the distance between the water balloon and the center of Earth decreased. So, the gravitational potential energy stored between the water balloon and Earth decreased as the water balloon fell toward Paul.
What evidence of a wildfire does this picture show?
[ "There is white ash on the ground.", "Some of the trees have green leaves." ]
0
This picture was taken after a wildfire. A wildfire happens when a natural area catches fire and burns.
closed choice
grade2
natural science
earth-science
Earth events
Find evidence of changes to Earth's surface
Evidence is information that tells you something happened. How do you look for evidence of a change to Earth's surface? There are many ways to find evidence of a change to Earth's surface. One way is to look at a picture that was taken after the change. Here are some examples of what the evidence for different changes might be: Cause of the change | Evidence of the change earthquake | cracks in the ground; houses with broken walls and roofs volcanic eruption | melted rock on Earth's surface; smoke coming out of a hole in the ground erosion | a canyon with a river flowing through it; a river carrying sand and mud Be careful when you are looking for evidence! A picture of Earth's surface can contain a lot of information. Some of that information might be evidence of a change to the surface, but some of it is not! For example, a picture taken after an earthquake might show a blue sky. But the color of the sky is not evidence of an earthquake. So, that information is not evidence that an earthquake happened.
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Does this passage describe the weather or the climate? Manuel noticed that the sky was filled with cumulus clouds every day last week.
[ "weather", "climate" ]
0
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.
closed choice
grade4
natural science
earth-science
Weather and climate
What's the difference between weather and 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 text carefully. Manuel noticed that the sky was filled with cumulus clouds every day last week. This passage tells you about the clouds Manuel saw last week. It describes the atmosphere at a certain place and time. So, this passage describes the weather.
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Which job does the circulatory system do?
[ "It breaks down food into small pieces.", "It helps remove carbon dioxide waste from the body." ]
1
closed choice
grade4
natural science
biology
Animals
Body systems: circulation and respiration
To stay alive, animal cells must get water and oxygen. Animal cells also produce carbon dioxide, a waste that must be removed. An animal's respiratory and circulatory systems work together to do these jobs. An animal's respiratory system is made up of organs that work together to bring in oxygen gas from the environment. The respiratory system also removes carbon dioxide gas from the animal's body. Some animals have lungs to exchange oxygen and carbon dioxide with the air. Other animals have gills to exchange oxygen and carbon dioxide with water. An animal's circulatory system is made up of organs that work together to move blood through its body. The heart pumps blood through blood vessels throughout the body. As blood moves through blood vessels, it delivers oxygen, nutrients from food, and water to cells. Blood also absorbs waste, including carbon dioxide. When the blood is pumped into the lungs or gills, it releases carbon dioxide and absorbs oxygen.
The circulatory system brings oxygen, nutrients, and water to cells. It also helps remove carbon dioxide waste. The circulatory system does not break down food into small pieces. This job is done by the digestive system. After the digestive system breaks down food, blood vessels in the intestines absorb the nutrients from the food. The blood then carries the nutrients to cells throughout the body.
Is granodiorite a mineral?
[ "yes", "no" ]
1
Granodiorite has the following properties: not made by organisms no fixed crystal structure solid not a pure substance naturally occurring
yes or no
grade5
natural science
earth-science
Rocks and minerals
Identify rocks and minerals
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.
Granodiorite does not have all the properties of a mineral. So, granodiorite is not a mineral.
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Would you find the word wild on a dictionary page with the following guide words? well - word
[ "no", "yes" ]
1
yes or no
grade2
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on.
Put the words in alphabetical order. Since wild is between the guide words well - word, it would be found on that page.
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Is the following trait inherited or acquired? Reggie has a scar on his left hand.
[ "acquired", "inherited" ]
0
closed choice
grade5
natural science
biology
Traits and heredity
Identify inherited and acquired traits
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Children do not inherit their parents' acquired traits.
Children do not inherit their parent's scars. Instead, scars are caused by the environment. People can get scars after they get hurt. So, having a scar is an acquired trait.
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Would you find the word mumble on a dictionary page with the following guide words? medicine - mid
[ "yes", "no" ]
1
yes or no
grade4
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since mumble is not between the guide words medicine - mid, it would not be found on that page.
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Select the one animal that has all of the amphibian traits listed above.
[ "African elephants have thin hair covering their body. Female elephants feed their offspring milk. Elephants live in groups called herds. The oldest female in the herd is usually the leader.", "Gray tree frogs hatch from eggs without shells. They live underwater when they are tadpoles. They move onto land when they become adults. The moist skin of adult gray tree frogs can be green or gray. The color of their skin helps them hide on rocks or plants." ]
1
Amphibians are a group of animals with similar traits. The following traits can be used to identify amphibians: They spend part of their lives in water and part on land. They have moist skin. They make eggs with no shells. Observe the animals and read the descriptions.
closed choice
grade4
natural science
biology
Classification
Use evidence to classify mammals, birds, fish, reptiles, and amphibians
Scientists sort animals with similar traits into groups. This is called classification. Classification helps scientists learn about how animals live. How do scientists classify animals? First, they make observations about an animal. Scientists observe the animal's traits, including its body parts and behavior. Then, scientists compare the animal's traits to other animals' traits. Scientists classify animals with similar traits into a group.
To decide if an animal is part of a group, look at the traits of the group. Amphibians have the following traits: They spend part of their lives in water and part on land. They have moist skin. They make eggs with no shells. Compare each animal's traits to the group's traits. Select the animal with traits similar to the group's traits. An African elephant has the following traits: It feeds its offspring milk. It has hair. An African elephant does not have all of the traits of an amphibian. An African elephant is a mammal. A gray tree frog has the following traits: It spends part of its life in water and part on land. It has moist skin. It makes eggs with no shells. A gray tree frog has the traits of an amphibian. A gray tree frog is an amphibian.
Select the organism in the same species as the black-headed gull.
[ "Chroicocephalus ridibundus", "Chroicocephalus serranus", "Crocodylus moreletii" ]
0
This organism is a black-headed gull. Its scientific name is Chroicocephalus ridibundus.
closed choice
grade8
natural science
biology
Classification and scientific names
Use scientific names to classify organisms
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 black-headed gull's scientific name is Chroicocephalus ridibundus. Chroicocephalus ridibundus is in the same genus as Chroicocephalus serranus, but they are not in the same species. Organisms in the same species have the same scientific names. Chroicocephalus ridibundus and Chroicocephalus serranus are different species within the same genus. Chroicocephalus ridibundus has the same scientific name as a black-headed gull. So, these organisms are in the same species. Crocodylus moreletii does not have the same scientific name as a black-headed gull. So, Chroicocephalus ridibundus and Crocodylus moreletii are not in the same species.
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Based on this information, what is Roxie's phenotype for the fur color trait?
[ "FF", "black fur" ]
1
In a group of Labrador retrievers, some individuals have black fur and others have brown fur. In this group, the gene for the fur color trait has two alleles. The allele F is for black fur, and the allele f is for brown fur. Roxie, a Labrador retriever from this group, has black fur. Roxie has two alleles for black fur.
closed choice
grade6
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait.
An organism's phenotype for a trait is its observable version of that trait. Roxie's observable version of the fur color trait is black fur. So, Roxie's phenotype for the fur color trait is black fur.
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Select the invertebrate.
[ "macaw", "domestic pig", "giant wood wasp", "tokay gecko" ]
2
Hint: Insects, spiders, and worms are invertebrates.
closed choice
grade5
natural science
biology
Classification
Identify vertebrates and invertebrates
Vertebrates and invertebrates are both groups of animals. A vertebrate has a backbone. The backbone is made of many bones in an animal's back. A vertebrate's backbone helps connect the different parts of its body. In the drawings below, each vertebrate's backbone is colored orange. An invertebrate does not have a backbone. In fact, invertebrates do not have any bones! Some invertebrates have an outer cover on their body called an exoskeleton. Other invertebrates have a soft body.
A macaw is a bird. Like other birds, a macaw is a vertebrate. It has a backbone. A domestic pig is a mammal. Like other mammals, a domestic pig is a vertebrate. It has a backbone. A giant wood wasp is an insect. Like other insects, a giant wood wasp is an invertebrate. It does not have a backbone. It has an exoskeleton. A tokay gecko is a reptile. Like other reptiles, a tokay gecko is a vertebrate. It has a backbone.
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Which basketball has a higher temperature?
[ "the basketball with more thermal energy", "the basketball with less thermal energy" ]
0
Two basketballs are identical except for their thermal energies.
closed choice
grade5
natural science
physics
Heat and thermal energy
How are temperature and mass related to thermal energy?
Matter is made of tiny particles called atoms. Atoms are always moving. The energy of moving atoms is called thermal energy. The total amount of thermal energy in matter depends on three things: the type of matter, the amount of matter, and how fast the atoms are moving. Temperature measures how hot or cold matter is. If the atoms in matter move faster, the temperature goes up. The matter now has both more thermal energy and a higher temperature. What happens if the amount of matter changes? A 2-kilogram brick at 70°F has twice as much thermal energy as a 1-kilogram brick at 70°F. The two bricks have the same temperature, but the larger brick has twice as many atoms. So, it has twice as much thermal energy.
The two basketballs are made of the same material and have the same mass. So, the basketball with more thermal energy has a higher temperature.
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Which is a compound sentence?
[ "China grows most of the wheat in the world.", "Mr. Everett cleans the chimney, and Mrs. Everett washes the car." ]
1
closed choice
grade3
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple or compound?
A simple sentence is a sentence with only one subject and predicate. The pitcher threw the ball to first base. A compound sentence is two simple sentences joined by a comma and a conjunction such as and, but, or, or so. The pitcher threw the ball, and the batter hit it. Some simple sentences have a compound subject or a compound predicate, but they are not compound sentences. Anna and James will watch the fireworks tonight. This simple sentence has a compound subject, Anna and James. The singers bowed and walked off the stage. This simple sentence has a compound predicate, bowed and walked off the stage. Some simple sentences have introductory phrases, but they are not compound sentences. The introductory phrase is part of the predicate. In the winter, Farmer Ben wears his heavy coat. This is a simple sentence. There is one subject, Farmer Ben, and one predicate, wears his heavy coat in the winter.
The first sentence is the compound sentence. It is made up of two simple sentences joined by a comma and the conjunction and. Mr. Everett cleans the chimney, and Mrs. Everett washes the car.
Identify the question that Cooper's experiment can best answer.
[ "Can pennies hold more drops of water mixed with dish soap or water mixed with hand soap?", "Can pennies hold more drops of pure water or water mixed with hand soap?" ]
1
The passage below describes an experiment. Read the passage and then follow the instructions below. Cooper used a dropper to put equal-sized drops of pure water, one at a time, onto a penny. The drops stayed together and formed a dome on the penny's surface. Cooper recorded the number of drops he could add before the water spilled over the edge of the penny. Then, he rinsed and dried the penny, and repeated the test using water mixed with hand soap. He repeated these trials on nine additional pennies. Cooper compared the average number of pure water drops to the average number of water drops mixed with hand soap that he could add to a penny before the water spilled over. Figure: a dome of water on the surface of a penny.
closed choice
grade6
natural science
science-and-engineering-practices
Designing experiments
Identify the experimental question
Experiments can be designed to answer specific questions. How can you identify the questions that a certain experiment can answer? In order to do this, you need to figure out what was tested and what was measured during the experiment. Imagine an experiment with two groups of daffodil plants. One group of plants was grown in sandy soil, and the other was grown in clay soil. Then, the height of each plant was measured. First, identify the part of the experiment that was tested. The part of an experiment that is tested usually involves the part of the experimental setup that is different or changed. In the experiment described above, each group of plants was grown in a different type of soil. So, the effect of growing plants in different soil types was tested. Then, identify the part of the experiment that was measured. The part of the experiment that is measured may include measurements and calculations. In the experiment described above, the heights of the plants in each group were measured. Experiments can answer questions about how the part of the experiment that is tested affects the part that is measured. So, the experiment described above can answer questions about how soil type affects plant height. Examples of questions that this experiment can answer include: Does soil type affect the height of daffodil plants? Do daffodil plants in sandy soil grow taller than daffodil plants in clay soil? Are daffodil plants grown in sandy soil shorter than daffodil plants grown in clay soil?
Compare the average kinetic energies of the particles in each sample. Which sample has the higher temperature?
[ "neither; the samples have the same temperature", "sample A", "sample B" ]
2
The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.
closed choice
grade6
natural science
physics
Particle motion and energy
Identify how particle motion affects temperature and pressure
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 sample B has more mass than each particle in sample A. The particles in sample B also have a higher average speed than the particles in sample A. So, the particles in sample B have a higher average kinetic energy than the particles in sample A. Because the particles in sample B have the higher average kinetic energy, sample B must have the higher temperature.
Does this passage describe the weather or the climate?
[ "weather", "climate" ]
1
Figure: Prague. The Charles Bridge spans the Vltava River in Prague. Winters are windy in Prague, with average wind speeds of 11 miles per hour in December, January, and February. Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.
closed choice
grade6
natural science
earth-science
Weather and climate
Weather and climate around the world
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 Charles Bridge spans the Vltava River in Prague. Winters are windy in Prague, with average wind speeds of 11 miles per hour in December, January, and February. The underlined part of the passage tells you about the usual wind patterns in Prague. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.
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What information supports the conclusion that Joy inherited this trait?
[ "Joy and her mother both wear their hair in braids.", "Joy's parents have red hair. They passed down this trait to Joy." ]
1
Read the description of a trait. Joy has red hair.
closed choice
grade6
natural science
biology
Genes to traits
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down from biological parents to their offspring through genes. Genes are pieces of hereditary material that contain the instructions that affect inherited traits. Offspring receive their genes, and therefore gain their inherited traits, from their biological parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Parents do not pass acquired traits down to their offspring.
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Which logical fallacy is used in the text? A rainbow appeared in the sky the day before basketball tryouts, and I made the team! If there's a rainbow when I try out in the spring, I'm sure I'll make the team again.
[ "ad hominem: a personal attack against one's opponent", "false causation: the assumption that because two things happened together, one caused the other" ]
1
closed choice
grade8
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fallacy may present irrelevant information: Fallacy | Description ad hominem | a personal attack meant to discredit one's opponent appeal to nature | an argument that assumes the natural choice is always the best choice bandwagon fallacy | an argument that assumes the popular choice is always the best choice circular reasoning | an argument that supports a claim with the claim itself guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something red herring | the use of a completely unrelated topic in support of a claim A logical fallacy may misrepresent the issues at hand: Fallacy | Description false causation | the assumption that because two things happened together, one caused the other false dichotomy | an argument that presents only two choices when more options exist hasty generalization | a very broad claim based on very little evidence straw man | a misrepresentation of an opponent's position that makes it easier to argue against
The text argues that the rainbow is responsible for the speaker making the basketball team. However, even though the speaker made the team after the rainbow appeared, that doesn't necessarily mean that the rainbow was responsible. This illustrates a type of logical fallacy known as false causation.
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Which is a run-on sentence?
[ "All the things in the back of the closet.", "Jayla is from Springdale now she lives in Dover." ]
1
closed choice
grade3
language science
writing-strategies
Sentences, fragments, and run-ons
Is it a complete sentence, a fragment, or a run-on?
A sentence is a group of words that forms a complete thought. It has both a subject and a verb. My friends walk along the path. A sentence fragment is a group of words that does not express a complete thought. It is usually missing a subject or a verb. Knows the answer. This is a sentence fragment. It is missing a subject. Who knows the answer? She knows the answer. The bright red car. This is a sentence fragment. It is missing a verb. What did the bright red car do? The bright red car stopped. A run-on sentence is made up of two sentences that are joined without end punctuation or with just a comma. I knocked on the door it opened. It started raining, we ran inside. To fix a run-on sentence, separate it into two sentences. Add end punctuation after the first sentence, and capitalize the second sentence. I knocked on the door. It opened. It started raining. We ran inside. You can also fix a run-on sentence by rewriting it as a compound sentence. A compound sentence is two sentences joined by a comma and a conjunction such as and, but, or, or so. I knocked on the door, and it opened. It started raining, so we ran inside.
Jayla is from Springdale now she lives in Dover is a run-on sentence. It has two sentences that are joined without end punctuation: Jayla is from Springdale and Now she lives in Dover.
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Which phrase has a more positive connotation?
[ "a cozy house", "a small house" ]
0
closed choice
grade4
language science
vocabulary
Shades of meaning
Positive and negative connotation
Connotation is the feeling or idea that goes along with a word or phrase. Some words are close in meaning but have different connotations. For example, think about the words eager and impatient. They both mean wanting something to happen, but they have different connotations. Eager has a positive connotation. It is a nice word. An eager person is happy and excited. Impatient has a negative connotation. It is not a nice word. An impatient person is often pushy and demanding.
A cozy house has a more positive connotation. A cozy house is small, but it is comfortable and warm.
Select the organism in the same species as the marbled salamander.
[ "Taricha torosa", "Taricha granulosa", "Ambystoma opacum" ]
2
This organism is a marbled salamander. Its scientific name is Ambystoma opacum.
closed choice
grade7
natural science
biology
Classification and scientific names
Use scientific names to classify organisms
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 marbled salamander's scientific name is Ambystoma opacum. Taricha granulosa does not have the same scientific name as a marbled salamander. So, Ambystoma opacum and Taricha granulosa are not in the same species. Ambystoma opacum has the same scientific name as a marbled salamander. So, these organisms are in the same species. Taricha torosa does not have the same scientific name as a marbled salamander. So, Ambystoma opacum and Taricha torosa are not in the same species.
Which animal's skin is better adapted as a warning sign to ward off predators?
[ "flamboyant cuttlefish", "impala" ]
0
Opalescent nudibranchs have stinging cells in their brightly colored skin. The bright colors serve as a warning sign that the animal is toxic and dangerous. The 's skin is adapted to ward off predators. Figure: opalescent nudibranch.
closed choice
grade4
natural science
biology
Adaptations
Animal adaptations: skins and body coverings
An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The color, texture, and covering of an animal's skin are examples of adaptations. Animals' skins can be adapted in different ways. For example, skin with thick fur might help an animal stay warm. Skin with sharp spines might help an animal defend itself against predators.
Look at the picture of the opalescent nudibranch. The opalescent nudibranch has stinging cells in its brightly colored skin. Its skin is adapted to ward off predators. The bright colors serve as a warning sign that the opalescent nudibranch is toxic and dangerous. Now look at each animal. Figure out which animal has a similar adaptation. The flamboyant cuttlefish has a poisonous body with brightly colored skin. Its skin is adapted to ward off predators. The impala has yellow-brown fur. Its skin is not adapted to be a warning sign that wards off predators.
During this time, thermal energy was transferred from () to ().
[ "the surroundings . . . each pizza", "each pizza . . . the surroundings" ]
1
Celine was delivering two identical pizzas to a customer. While driving to the customer's house, Celine put one of the pizza boxes on top of the other one. This table shows how the temperature of each pizza changed over 15minutes.
closed choice
grade7
natural science
physics
Thermal energy
Compare thermal energy transfers
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.
Which property matches this object?
[ "scratchy", "flexible" ]
1
Select the better answer.
closed choice
grade3
natural science
physics
Materials
Identify properties of an object
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.
Look at the object. Think about each property. A flexible object can be folded or bent without breaking easily. The tent is flexible. A scratchy object is rough and itchy against your skin. The tent is not scratchy.
What is the name of the colony shown?
[ "New Hampshire", "Connecticut", "Vermont", "Georgia" ]
0
closed choice
grade4
social science
us-history
English colonies in North America
Identify the Thirteen Colonies
The colony is New Hampshire. During the colonial era, New Hampshire and New York both claimed the territory that would later become the state of Vermont. Vermont was never its own colony.
Will these magnets attract or repel each other?
[ "repel", "attract" ]
0
Two magnets are placed as shown. Hint: Magnets that attract pull together. Magnets that repel push apart.
closed choice
grade2
natural science
physics
Magnets
Identify magnets that attract or repel
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.
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How long is a basketball court?
[ "28 meters", "28 centimeters", "28 kilometers", "28 millimeters" ]
0
Select the best estimate.
closed choice
grade7
natural science
units-and-measurement
Units and measurement
Choose metric units of distance, mass, and volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. When you are using metric units, length can be written with units of millimeters, centimeters, meters, or kilometers. One meter contains 100 centimeters or 1,000 millimeters. So, 1 meter is larger than 1 centimeter, and 1 centimeter is larger than 1 millimeter. The tip of the pencil shown here is only 1 millimeter wide, but the pencil is about 16 centimeters long. A red fox is about 1 meter long. The Sydney Harbour Bridge in Australia is about 1,000 meters, or 1 kilometer, in length.
The best estimate for the length of a basketball court is 28 meters. 28 millimeters and 28 centimeters are too short. 28 kilometers is too long.
Identify the question that Jen's experiment can best answer.
[ "Do radishes grown under bright light get bigger than radishes grown under dim light?", "Do radish plants grown under bright light have more leaves than radish plants grown under dim light?" ]
0
The passage below describes an experiment. Read the passage and then follow the instructions below. Jen planted 20 radish plants in a greenhouse, putting each plant in its own pot. She placed ten of the pots under bright light and the other ten pots under dim light. Jen watered all the plants twice a day. After two months, she pulled the radish plants from the ground, threw away the leafy green tops, and measured the sizes of the radishes. She compared the sizes of the radishes grown under bright light to the sizes of the radishes grown under dim light. Figure: a radish plant in soil.
closed choice
grade7
natural science
science-and-engineering-practices
Designing experiments
Identify the experimental question
Experiments can be designed to answer specific questions. How can you identify the questions that a certain experiment can answer? In order to do this, you need to figure out what was tested and what was measured during the experiment. Imagine an experiment with two groups of daffodil plants. One group of plants was grown in sandy soil, and the other was grown in clay soil. Then, the height of each plant was measured. First, identify the part of the experiment that was tested. The part of an experiment that is tested usually involves the part of the experimental setup that is different or changed. In the experiment described above, each group of plants was grown in a different type of soil. So, the effect of growing plants in different soil types was tested. Then, identify the part of the experiment that was measured. The part of the experiment that is measured may include measurements and calculations. In the experiment described above, the heights of the plants in each group were measured. Experiments can answer questions about how the part of the experiment that is tested affects the part that is measured. So, the experiment described above can answer questions about how soil type affects plant height. Examples of questions that this experiment can answer include: Does soil type affect the height of daffodil plants? Do daffodil plants in sandy soil grow taller than daffodil plants in clay soil? Are daffodil plants grown in sandy soil shorter than daffodil plants grown in clay soil?
What location was involved in the triangular trade?
[ "China", "Great Britain" ]
1
By the 1700s, merchants in the Thirteen Colonies traded goods across the Atlantic Ocean in a pattern called triangular trade. Look at the map showing this trade. Then answer the question below.
closed choice
grade7
social science
us-history
The American Revolution
Causes of the American Revolution: introduction to mercantilism and the Navigation Acts
Look at the map. The arrows on the map show that goods moved to and from these locations: China was not involved in the triangular trade.
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What is the volume of a kitchen sink?
[ "26 milliliters", "26 liters" ]
1
Select the better estimate.
closed choice
grade5
natural science
units-and-measurement
Units and measurement
Choose metric units of volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Volume is a measurement of how much space something takes up. There are many different units of volume. When you are using metric units, volume may be written in units of milliliters or liters. There are 1,000 milliliters in 1 liter. So, 1 milliliter is much less than 1 liter. A raindrop has a volume of about 20 milliliters, while a large soda bottle has a volume of 2 liters. The flask shown here measures volumes up to 500 milliliters.
The better estimate for the volume of a kitchen sink is 26 liters. 26 milliliters is too little.