Question: Which better describes the tide pool ecosystems in Little Corona Beach?

Choices:
- It has daily flooding and draining of seawater. It also has water that is poor in nutrients.
- It has daily flooding and draining of seawater. It also has water that is rich in nutrients.

Figure: Little Corona Beach.
Little Corona Beach is in southern California. It has many tide pool ecosystems.

natural science

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

Solution: A tide pool is a type of ecosystem. Tide pool ecosystems have the following features: daily flooding and draining of seawater, water that is rich in nutrients, and many different types of organisms. So, the tide pool ecosystems in Little Corona Beach have daily flooding and draining of seawater. They also have water that is rich in nutrients.


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

Choices:
- The magnitude of the magnetic force is greater in Pair 2.
- The magnitude of the magnetic force is greater in Pair 1.
- The magnitude of the magnetic force is the same in both pairs.

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.

natural science

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

Solution:
The magnets in Pair 1 attract. The magnets in Pair 2 repel. But whether the magnets attract or repel affects only the direction of the magnetic force. It does not affect the magnitude of the magnetic force.
Distance affects the magnitude of the magnetic force. When there is a smaller distance between magnets, the magnitude of the magnetic force between them is greater.
There is a smaller distance between the magnets in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is greater in Pair 2 than in Pair 1.


Question: Is Myrmarachne maxillosa made up of one cell?

Choices:
- yes
- no

This organism is Myrmarachne maxillosa. It is a member of the animal kingdom.
Myrmarachne maxillosa is a spider. But its body shape mimics, or copies, the shape of an ant. Mimicking an ant helps M. maxillosa avoid predators that eat spiders. You can tell that M. maxillosa is a spider by counting its legs. Spiders have eight legs, and ants have just six.

natural science

Describe, classify, and compare kingdoms

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

Solution: Myrmarachne maxillosa is an animal. Animals are made up of many cells.


Question: Which fish's mouth is also adapted for tearing through meat?

Choices:
- parrotfish
- starry moray

Sand tiger sharks eat turtles, dolphins, and other fish. The mouth of the tiger shark is adapted to tear through meat.
Figure: sand tiger shark.

natural science

Animal adaptations: beaks, mouths, and necks

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

Solution:
Look at the picture of the sand tiger shark.
The sand tiger shark has a large mouth and sharp teeth. Its mouth is adapted for tearing through meat. The sand tiger shark uses its teeth to cut up meat into pieces it can swallow.
Now look at each animal. Figure out which animal has a similar adaptation.
The starry moray has a large mouth and sharp teeth. Its mouth is adapted for tearing through meat.
The parrotfish has a small mouth and small teeth. Its mouth is not adapted for tearing through meat. The parrotfish uses its mouth to eat corals.


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

Choices:
- sample A
- sample B
- neither; the samples have the same temperature

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.

natural science

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.

Solution:
The particles in both samples have the same average speed, but each particle in sample B has more mass than each particle 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.


Question: Based on the arrows, which of the following living things is an omnivore?

Choices:
- kelp bass
- zooplankton

Below is a food web from an ocean ecosystem. The ecosystem is in Monterey Bay, off the coast of California.
A food web is a model that shows how the matter eaten by living things moves through an ecosystem. The arrows show how matter moves through the food web.

natural science

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

Solution:
Omnivores are consumers that eat both producers and other consumers. So, an omnivore has arrows pointing to it from at least one producer and at least one consumer.
The zooplankton has only one arrow pointing to it. This arrow starts from the phytoplankton. So, the zooplankton is a consumer but not an omnivore.
The kelp bass has an arrow pointing to it from the kelp, which is a producer. The kelp bass also has arrows pointing to it from the zooplankton and the plainfin midshipman, which are both consumers. The kelp bass eats a producer and consumers, so it is an omnivore.


Question: What is the name of the colony shown?

Choices:
- Iowa
- Connecticut
- Virginia
- Maine

social science

Solution: The colony is Connecticut.


Question: Which statement is true about seeds?

Choices:
- A plant's flowers make seeds.
- A plant's fruit makes seeds.

natural science

Describe and construct flowering plant life cycles

Many plants have flowers. These plants can use their flowers to reproduce, or make new plants like themselves. How do plants use their flowers to reproduce?
First, the male part of the flower makes pollen, and the female part makes eggs. Animals, wind, or water can move pollen. Pollination is what happens when pollen is moved to the female part of the flower.
After pollination, sperm from the pollen can combine with the eggs. This is called fertilization. The fertilized eggs grow into seeds. The fruit grows around the seeds. Later, a seed can fall out of the fruit. It can germinate, or start to grow into a new plant.

Solution:
Flowers make seeds. After a flower is pollinated, male cells from the pollen combine with eggs. This is called fertilization. The fertilized eggs grow into seeds.
The fruit can grow around the seeds. But the fruit does not make seeds. Both the fruit and the seeds grow from parts of the flower.


Question: In this food web, which organism contains matter that eventually moves to the mushroom?

Choices:
- brown lemming
- bilberry

Below is a food web from a tundra ecosystem in Nunavut, a territory in Northern Canada.
A food web models how the matter eaten by organisms moves through an ecosystem. The arrows in a food web represent how matter moves between organisms in an ecosystem.

natural science

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

Solution: Use the arrows to follow how matter moves through this food web. For each answer choice, try to find a path of arrows to the mushroom.There is one path matter can take from the bilberry to the mushroom: bilberry->grizzly bear->mushroom. There is one path matter can take from the grizzly bear to the mushroom: grizzly bear->mushroom. There are two paths matter can take from the barren-ground caribou to the mushroom: barren-ground caribou->mushroom. barren-ground caribou->grizzly bear->mushroom. There are two paths matter can take from the lichen to the mushroom: lichen->barren-ground caribou->mushroom. lichen->barren-ground caribou->grizzly bear->mushroom. brown lemming. There are three arrows pointing from the brown lemming to other organisms. One arrow points to the Arctic fox. The only arrow pointing from the Arctic fox leads to the earthworm. The second arrow pointing from the brown lemming leads to the short-tailed weasel. The only arrow pointing from the short-tailed weasel leads to the snowy owl. The only arrow pointing from the snowy owl leads to the earthworm. The third arrow pointing from the brown lemming leads to the parasitic jaeger. The only arrow pointing from the parasitic jaeger leads to the rough-legged hawk. The only arrow pointing from the rough-legged hawk leads to the earthworm. No arrows point from the earthworm to any other organisms. So, in this food web, matter does not move from the brown lemming to the mushroom..


Question: Select the organism in the same genus as the spot-billed pelican.

Choices:
- Ardea herodias
- Pelecanus philippensis
- Bubo scandiacus

This organism is a spot-billed pelican. Its scientific name is Pelecanus philippensis.

natural science

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.

Solution:
A spot-billed pelican's scientific name is Pelecanus philippensis. The first word of its scientific name is Pelecanus.
Bubo scandiacus is in the genus Bubo. The first word of its scientific name is Bubo. So, Bubo scandiacus and Pelecanus philippensis are not in the same genus.
This organism and the spot-billed pelican are in the same genus and the same species! Both organisms have the same scientific name, Pelecanus philippensis.
Ardea herodias is in the genus Ardea. The first word of its scientific name is Ardea. So, Ardea herodias and Pelecanus philippensis are not in the same genus.


Question: What can Bryce and Victor trade to each get what they want?

Choices:
- Victor can trade his broccoli for Bryce's oranges.
- Bryce can trade his tomatoes for Victor's broccoli.
- Victor can trade his almonds for Bryce's tomatoes.
- Bryce can trade his tomatoes for Victor's carrots.

Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another.
Bryce and Victor open their lunch boxes in the school cafeteria. Neither Bryce nor Victor got everything that they wanted. The table below shows which items they each wanted:

Look at the images of their lunches. Then answer the question below.
Bryce's lunch Victor's lunch

social science

Solution:
Look at the table and images.
Bryce wants broccoli. Victor wants tomatoes. They can trade tomatoes for broccoli to both get what they want. Trading other things would not help both people get more items they want.


Question: What location was involved in the triangular trade?

Choices:
- western Africa
- China

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.

social science

Causes of the American Revolution: introduction to mercantilism and the Navigation Acts

Solution:
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.


Question: Does Asimina triloba have cells that have a nucleus?

Choices:
- yes
- no

This organism is Asimina triloba. It is a member of the plant kingdom.
Asimina triloba is commonly called the pawpaw. Pawpaw trees grow in the southeastern part of the United States. They have large, sweet fruit. The fruit is sometimes called a prairie banana.

natural science

Describe, classify, and compare kingdoms

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

Solution: Asimina triloba is a plant. Plant cells have a nucleus.


Question: Which of the following could Hector's test show?

Choices:
- whether the filter was clogged
- the amount of bacteria in the water before it was filtered
- whether an inexpensive filter would become clogged more often

People can use the engineering-design process to develop solutions to problems. One step in the process is testing if a potential solution meets the requirements of the design.
The passage below describes how the engineering-design process was used to test a solution to a problem. Read the passage. Then answer the question below.

Hector was . At the plant, an expensive filter was used to remove disease-causing bacteria from the water. But over time, the filter would become clogged with bacteria. If the filter became clogged, the water would not move through quickly enough. Hector had to decide when the filter was too clogged and needed to be replaced. So, during his inspection, Hector checked the filter by measuring how quickly water moved through it.
Figure: an engineer at a water treatment plant.

natural science

Evaluate tests of engineering-design solutions

People can use the engineering-design process to develop solutions to problems. One step in the process is testing if a potential solution meets the requirements of the design. How can you determine what a test can show? You need to figure out what was tested and what was measured.
Imagine an engineer needs to design a bridge for a windy location. She wants to make sure the bridge will not move too much in high wind. So, she builds a smaller prototype, or model, of a bridge. Then, she exposes the prototype to high winds and measures how much the bridge moves.
First, identify what was tested. A test can examine one design, or it may compare multiple prototypes to each other. In the test described above, the engineer tested a prototype of a bridge in high wind.
Then, identify what the test measured. One of the criteria for the bridge was that it not move too much in high winds. The test measured how much the prototype bridge moved.
Tests can show how well one or more designs meet the criteria. The test described above can show whether the bridge would move too much in high winds.


Question: Which trait did Pentasteria have? Select the trait you can observe on the fossil.

Choices:
- red skin
- a long tube-shaped body
- five arms

This picture shows a fossil of an ancient animal called Pentasteria.
Pentasteria lived in the ocean over 190,000,000 years ago.

natural science

The way an organism looks or acts is called a trait. Scientists use fossils to learn more about the traits of ancient organisms.
Fossils can preserve the remains of body parts and activities. A fossil of a body part, such as a tail or a wing, can tell you what an organism looked like. A fossil of an organism's activities, such as a burrow or a footprint, can tell you about the organism's behavior.
Here are three examples of fossils and the traits that you can observe from them:
This is a fossil of an animal. This fossil tells you that the animal had a spiral-shaped shell.
This is a fossil of a plant. This fossil tells you that the plant had small leaves arranged in a branched pattern.
This is a fossil of an animal's footprint. This fossil tells you that the animal could walk on land.
An organism's fossil may not show all of the organism's traits. This is because most body parts are destroyed during fossil formation. When an organism's body turns into a fossil, only a few body parts are usually preserved.


Question: What can Sadie and Kira trade to each get what they want?

Choices:
- Kira can trade her almonds for Sadie's tomatoes.
- Sadie can trade her tomatoes for Kira's broccoli.
- Kira can trade her broccoli for Sadie's oranges.
- Sadie can trade her tomatoes for Kira's sandwich.

Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another.
Sadie and Kira open their lunch boxes in the school cafeteria. Both of them could be happier with their lunches. Sadie wanted broccoli in her lunch and Kira was hoping for tomatoes. Look at the images of their lunches. Then answer the question below.

social science

Solution:
Sadie wanted broccoli in her lunch and Kira was hoping for tomatoes. Look at the labeled part of the images.
Sadie has tomatoes. Kira has broccoli. They can trade tomatoes for broccoli to both be happier. Trading other things would not help either person get more items they want.


Question: Select the amphibian below.

Choices:
- red salamander
- koala

Amphibians have moist skin and begin their lives in water. An African bullfrog is an example of an amphibian.

natural science

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.

Solution:
A koala is a mammal. It has fur and feeds its young milk.
A red salamander is an amphibian. It has moist skin and begins its life in water.


Question: Which property do these three objects have in common?

Choices:
- shiny
- bumpy
- bouncy

natural science

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

Solution:
Look at each object.
For each object, decide if it has that property.
A bouncy object will bounce back from the floor if you drop it. All three objects are bouncy.
A shiny object reflects a lot of light. You can usually see your reflection in a shiny object. The basketball is not shiny.
A bumpy object is covered in lumps and bumps. The rubber ball is not bumpy.
The property that all three objects have in common is bouncy.


Question: What is the capital of Wyoming?

Choices:
- Cheyenne
- Nashville
- Dover
- Laramie

social science

Solution: Cheyenne is the capital of Wyoming.


Question: Which animal's feet are also adapted for walking on large, floating leaves?

Choices:
- New Zealand falcon
- wattled jacana

s live near rivers and lakes. They eat insects and snails that live on plants floating on the surface of the water.
The feet of the jacana are adapted for walking on large, floating leaves. The jacana uses its feet to spread its weight out over a wide area. This helps the bird walk on the leaves without sinking into the water.
Figure: African jacana.

natural science

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors.
The shape of an animal's 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.

Solution:
Look at the picture of the African jacana.
The African jacana uses its toes to spread its weight out over a large area. This can help it walk on leaves without sinking into the water.
Now look at each animal. Figure out which animal has a similar adaptation.
The wattled jacana has long, thin toes on its feet. Its feet are adapted for walking on floating leaves.
The New Zealand falcon has medium-sized toes with sharp claws. Its feet are not adapted for walking on floating leaves. The New Zealand falcon uses its feet to grab prey.


Question: What is the capital of Wisconsin?

Choices:
- Milwaukee
- Madison
- Cheyenne
- Green Bay

social science

Solution: Madison is the capital of Wisconsin.


Question: Which animal's mouth is also adapted for bottom feeding?

Choices:
- bat ray
- clown triggerfish

Armored catfish eat plants and small invertebrates. They are bottom feeders. Bottom feeders find their food at the bottom of rivers, lakes, and the ocean.
The catfish's mouth is located on the underside of its head and points downward. Its mouth is adapted for bottom feeding.
Figure: armored catfish.

natural science

Animal adaptations: beaks, mouths, and necks

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

Solution:
Look at the picture of the armored catfish.
The armored catfish's mouth is located on the underside of its head and points downward. Its mouth is adapted for bottom feeding. The armored catfish uses its mouth to find food hidden in the sediment at the bottom of rivers and streams.
Now look at each animal. Figure out which animal has a similar adaptation.
The bat ray's mouth is located on the underside of its head. Its mouth points downward. Its mouth is adapted for bottom feeding.
The clown triggerfish's mouth is not located on the underside of its head. Its mouth is not adapted for bottom feeding.


Question: What can Edwin and Brenda trade to each get what they want?

Choices:
- Brenda can trade her almonds for Edwin's tomatoes.
- Edwin can trade his tomatoes for Brenda's carrots.
- Edwin can trade his tomatoes for Brenda's broccoli.
- Brenda can trade her broccoli for Edwin's oranges.

Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another.
Edwin and Brenda open their lunch boxes in the school cafeteria. Neither Edwin nor Brenda got everything that they wanted. The table below shows which items they each wanted:

Look at the images of their lunches. Then answer the question below.
Edwin's lunch Brenda's lunch

social science

Solution:
Look at the table and images.
Edwin wants broccoli. Brenda wants tomatoes. They can trade tomatoes for broccoli to both get what they want. Trading other things would not help both people get more items they want.


Question: Which of these states is farthest south?

Choices:
- Washington
- Iowa
- North Dakota
- Nevada

social science

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

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


Question: Which of the following could Camille and Lucy's test show?

Choices:
- if a new batch of concrete was firm enough to use
- if the concrete from each batch took the same amount of time to dry

People can use the engineering-design process to develop solutions to problems. One step in the process is testing if a potential solution meets the requirements of the design.
The passage below describes how the engineering-design process was used to test a solution to a problem. Read the passage. Then answer the question below.

Camille and Lucy were making batches of concrete for a construction project. To make the concrete, they mixed together dry cement powder, gravel, and water. Then, they checked if each batch was firm enough using a test called a slump test.
They poured some of the fresh concrete into an upside-down metal cone. They left the concrete in the metal cone for 30 seconds. Then, they lifted the cone to see if the concrete stayed in a cone shape or if it collapsed. If the concrete in a batch collapsed, they would know the batch should not be used.
Figure: preparing a concrete slump test.

natural science

Evaluate tests of engineering-design solutions

People can use the engineering-design process to develop solutions to problems. One step in the process is testing if a potential solution meets the requirements of the design. How can you determine what a test can show? You need to figure out what was tested and what was measured.
Imagine an engineer needs to design a bridge for a windy location. She wants to make sure the bridge will not move too much in high wind. So, she builds a smaller prototype, or model, of a bridge. Then, she exposes the prototype to high winds and measures how much the bridge moves.
First, identify what was tested. A test can examine one design, or it may compare multiple prototypes to each other. In the test described above, the engineer tested a prototype of a bridge in high wind.
Then, identify what the test measured. One of the criteria for the bridge was that it not move too much in high winds. The test measured how much the prototype bridge moved.
Tests can show how well one or more designs meet the criteria. The test described above can show whether the bridge would move too much in high winds.


Question: Select the organism in the same genus as the European nightjar.

Choices:
- Caprimulgus europaeus
- Haliaeetus leucocephalus
- Ulex europaeus

This organism is a European nightjar. Its scientific name is Caprimulgus europaeus.

natural science

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.

Solution:
A European nightjar's scientific name is Caprimulgus europaeus. The first word of its scientific name is Caprimulgus.
Haliaeetus leucocephalus is in the genus Haliaeetus. The first word of its scientific name is Haliaeetus. So, Haliaeetus leucocephalus and Caprimulgus europaeus are not in the same genus.
Ulex europaeus and Caprimulgus europaeus are not in the same genus.
These organisms are not in the same genus, but part of their scientific names is the same. Ulex europaeus and Caprimulgus europaeus have the same species name within their genus, europaeus. But the first words of their scientific names are different. Ulex europaeus is in the genus Ulex, and Caprimulgus europaeus is in the genus Caprimulgus.
This organism and the European nightjar are in the same genus and the same species! Both organisms have the same scientific name, Caprimulgus europaeus.


Question: Which property do these three objects have in common?

Choices:
- sticky
- blue
- bouncy

natural science

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

Solution:
Look at each object.
For each object, decide if it has that property.
A bouncy object will bounce back from the floor if you drop it. None of the objects are bouncy.
A sticky object can attach or stick to other things. The toothpaste is sticky, but the slippers and the track suit are not.
Blue is a color.
This color is blue. All three objects are blue.
The property that all three objects have in common is blue.


Question: What can Justine and Caleb trade to each get what they want?

Choices:
- Caleb can trade his almonds for Justine's tomatoes.
- Justine can trade her tomatoes for Caleb's broccoli.
- Caleb can trade his broccoli for Justine's oranges.
- Justine can trade her tomatoes for Caleb's carrots.

Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another.
Justine and Caleb open their lunch boxes in the school cafeteria. Neither Justine nor Caleb got everything that they wanted. The table below shows which items they each wanted:

Look at the images of their lunches. Then answer the question below.
Justine's lunch Caleb's lunch

social science

Solution:
Look at the table and images.
Justine wants broccoli. Caleb wants tomatoes. They can trade tomatoes for broccoli to both get what they want. Trading other things would not help both people get more items they want.


Question: What is the capital of West Virginia?

Choices:
- Huntington
- Charleston
- Concord
- Memphis

social science

Identify state capitals of the Southeast

Solution: Charleston is the capital of West Virginia.


Question: What is the capital of Colorado?

Choices:
- Providence
- Baton Rouge
- Denver
- Colorado Springs

social science

Solution: Denver is the capital of Colorado.


Question: What is the capital of Nevada?

Choices:
- Frankfort
- Juneau
- Carson City
- Huntington

social science

Solution: Carson City is the capital of Nevada.


Question: Select the organism in the same species as the snowy owl.

Choices:
- Bubo scandiacus
- Falco tinnunculus
- Ardea alba

This organism is a snowy owl. Its scientific name is Bubo scandiacus.

natural science

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.

Solution:
A snowy owl's scientific name is Bubo scandiacus.
Falco tinnunculus does not have the same scientific name as a snowy owl. So, Bubo scandiacus and Falco tinnunculus are not in the same species.
Bubo scandiacus has the same scientific name as a snowy owl. So, these organisms are in the same species.
Ardea alba does not have the same scientific name as a snowy owl. So, Bubo scandiacus and Ardea alba are not in the same species.


Question: Which ocean is highlighted?

Choices:
- the Atlantic Ocean
- the Indian Ocean
- the Arctic Ocean
- the Pacific Ocean

social science

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

Solution: This is the Atlantic Ocean.


Question: Identify the question that Joe's experiment can best answer.

Choices:
- Do more bacteria grow in liquid with cinnamon than in liquid without cinnamon?
- Does temperature affect how much bacteria can grow in liquid?

The passage below describes an experiment. Read the passage and then follow the instructions below.

Joe mixed bacteria into a nutrient-rich liquid where the bacteria could grow. He poured four ounces of the mixture into each of ten glass flasks. In five of the ten flasks, he also added one teaspoon of cinnamon. He allowed the bacteria in the flasks to grow overnight in a 37°C room. Then, Joe used a microscope to count the number of bacteria in a small sample from each flask. He compared the amount of bacteria in the liquid with cinnamon to the amount of bacteria in the liquid without cinnamon.
Figure: flasks of liquid for growing bacteria.

natural science

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?


Question: Which ocean is highlighted?

Choices:
- the Atlantic Ocean
- the Indian Ocean
- the Southern Ocean
- the Pacific Ocean

social science

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

Solution: This is the Pacific Ocean.


Question: Which term matches the picture?

Choices:
- operant conditioning
- classical conditioning

Read the text.
A conditioned response occurs when an animal learns to associate two events that were not originally related. For example, a dog will naturally salivate at the smell of food (an unconditioned response). However, if a dog learns that the sound of a ringing bell is a sure sign that dinner is coming, it will begin to react to the sound of that bell the same way it reacts to the smell of food (a conditioned response). This is called classical conditioning.
Operant conditioning is a process like classical conditioning. However, in classical conditioning, the events that an animal learns to associate are not under the animal's voluntary control. In operant conditioning, an external event that is either a reward or punishment becomes linked with a voluntary behavior. For example, a student who receives a gold star for sitting quietly is more likely to choose to sit quietly in the future. The behavior (sitting quietly) has become linked in the student's mind with the reward that it produced in the past. Animal trainers rely on operant conditioning to encourage desired behaviors and discourage unwanted ones.

language science

Determine the meaning of domain-specific words with pictures

Solution: A dog receiving a treat for sitting and staying is an example of operant conditioning. The treat is a reward that encourages wanted behavior, like sitting, in the future.


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

Choices:
- sample A
- neither; the samples have the same temperature
- sample B

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.

natural science

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.

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


Question: Which is the main persuasive appeal used in this ad?

Choices:
- logos (reason)
- ethos (character)
- pathos (emotion)

language science

Identify appeals to ethos, pathos, and logos in advertisements

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

Solution: The ad appeals to pathos, or emotion. It triggers feelings of pity for shelter animals.


Question: Which continent is highlighted?

Choices:
- Asia
- South America
- North America
- Australia

social science

A continent is one of the major land masses on the earth. Most people say there are seven continents.

Solution: This continent is Asia.


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

Choices:
- The magnitude of the magnetic force is smaller in Pair 1.
- The magnitude of the magnetic force is smaller in Pair 2.
- The magnitude of the magnetic force is the same in both pairs.

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.

natural science

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

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


Question: Which animal's skin is better adapted as a warning sign to ward off predators?

Choices:
- lechwe
- blue poison dart frog

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.

natural science

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.

Solution:
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 blue poison dart frog has poisonous glands in its brightly colored skin. Its skin is adapted to ward off predators.
The lechwe has light-brown fur covering its skin. Its skin is not adapted to be a warning sign that wards off predators.


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

Choices:
- the surroundings . . . each battery
- each battery . . . the surroundings

Two friends bought phones that cost different amounts but had identical batteries. After using the phones for a while, both friends had to turn them off to let the batteries cool. This table shows how the temperature of each battery changed over 5minutes.

natural science

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

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


Question: Which rhetorical appeal is primarily used in this ad?

Choices:
- pathos (emotion)
- logos (reason)
- ethos (character)

language science

Identify appeals to ethos, pathos, and logos in advertisements

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

Solution: The ad appeals to pathos, or emotion, by associating the advertised product with feelings of belonging and familial love.


Question: Which property matches this object?

Choices:
- scratchy
- breakable

natural science

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

Solution:
Look at the object.
Think about each property.
A breakable object will break into pieces if you drop it. The sandpaper is not breakable.
A scratchy object is rough and itchy against your skin. The sandpaper is scratchy.


Question: Which country is highlighted?

Choices:
- Vanuatu
- the Marshall Islands
- Tuvalu
- Solomon Islands

social science

Identify and select countries of Oceania

Solution: This country is Solomon Islands.


Question: Which country is highlighted?

Choices:
- Dominica
- Saint Vincent and the Grenadines
- Jamaica
- Barbados

social science

Identify and select countries of the Caribbean

Solution: This country is Jamaica.


Question: Is a crown a solid, a liquid, or a gas?

Choices:
- a solid
- a gas
- a liquid

natural science

Classify matter as solid, liquid, or gas

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

Solution:
A crown is a solid. A solid has a size and shape of its own.
If you put a crown on your head, the crown will keep its shape.


Question: Which country is highlighted?

Choices:
- Papua New Guinea
- Australia
- the Federated States of Micronesia
- Palau

social science

Identify and select countries of Oceania

Solution: This country is the Federated States of Micronesia.


Question: Is a turtle shell a mineral?

Choices:
- no
- yes

A turtle shell has the following properties:
body part of a turtle
found in nature
no fixed crystal structure
not a pure substance
solid

natural science

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

Solution: A turtle shell does not have all the properties of a mineral. So, a turtle shell is not a mineral.


Question: What is the name of the colony shown?

Choices:
- New York
- Pennsylvania
- Delaware
- New Jersey

social science

Solution: The colony is Pennsylvania.


Question: Is the water in a fishbowl a solid, a liquid, or a gas?

Choices:
- a liquid
- a gas
- a solid

natural science

Classify matter as solid, liquid, or gas

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

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


Question: What is the capital of Alabama?

Choices:
- Bismarck
- Tallahassee
- Montgomery
- Birmingham

social science

Identify state capitals of the Southeast

Solution: Montgomery is the capital of Alabama.


Question: What is the capital of California?

Choices:
- Cheyenne
- Sacramento
- Honolulu
- Birmingham

social science

Solution: Sacramento is the capital of California.


Question: What can Mark and Valeria trade to each get what they want?

Choices:
- Mark can trade his tomatoes for Valeria's broccoli.
- Valeria can trade her broccoli for Mark's oranges.
- Mark can trade his tomatoes for Valeria's sandwich.
- Valeria can trade her almonds for Mark's tomatoes.

Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another.
Mark and Valeria open their lunch boxes in the school cafeteria. Both of them could be happier with their lunches. Mark wanted broccoli in his lunch and Valeria was hoping for tomatoes. Look at the images of their lunches. Then answer the question below.

social science

Solution:
Mark wanted broccoli in his lunch and Valeria was hoping for tomatoes. Look at the labeled part of the images.
Mark has tomatoes. Valeria has broccoli. They can trade tomatoes for broccoli to both be happier. Trading other things would not help either person get more items they want.


Question: What is the capital of Pennsylvania?

Choices:
- Harrisburg
- Pittsburgh
- Frankfort
- Providence

social science

Identify state capitals of the Northeast

Solution: Harrisburg is the capital of Pennsylvania.


Question: What is the capital of Vermont?

Choices:
- Bridgeport
- New Orleans
- Providence
- Montpelier

social science

Identify state capitals of the Northeast

Solution: Montpelier is the capital of Vermont.


Question: Which is this organism's scientific name?

Choices:
- brown-throated sloth
- Bradypus variegatus

This organism is a brown-throated sloth. It is also called Bradypus variegatus.

natural science

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

Solution:
Bradypus variegatus is written in italics. The first word is capitalized, and the second word is not.
So, Bradypus variegatus is the scientific name.


Question: What is the capital of Hawaii?

Choices:
- Honolulu
- Carson City
- Hilo
- Denver

social science

Solution: Honolulu is the capital of Hawaii.


Question: Which type of force from the woman's finger will knock over the domino?

Choices:
- pull
- push

A woman is going to topple a line of dominoes. Her finger applies a force to the first domino to knock it over.

natural science

A force is a push or a pull that one object applies to a second object.
The direction of a push is away from the object that is pushing.
The direction of a pull is toward the object that is pulling.

Solution: The woman's finger applies a force to the domino. This force will knock over the domino. The direction of this force is away from the woman's finger. This force is a push.


Question: Which property do these three objects have in common?

Choices:
- bouncy
- hard
- stretchy

natural science

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

Solution:
Look at each object.
For each object, decide if it has that property.
A hard object does not change shape when pressed or squeezed. All three objects are hard.
A stretchy object gets longer when you pull on it. None of the objects are stretchy.
A bouncy object will bounce back from the floor if you drop it. None of the objects are bouncy.
The property that all three objects have in common is hard.


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

Choices:
- neither; the samples have the same temperature
- sample A
- sample B

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.

natural science

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.

Solution:
Each particle in the two samples has the same mass, but the particles in sample A have a higher average speed than the particles in sample B. So, the particles in sample A have a higher average kinetic energy than the particles in sample B.
Because the particles in sample A have the higher average kinetic energy, sample A must have the higher temperature.


Question: Is quartzite a mineral?

Choices:
- no
- yes

Quartzite has the following properties:
not made by organisms
made mostly of quartz
no fixed crystal structure
found in nature
solid

natural science

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

Solution: Quartzite does not have all the properties of a mineral. So, quartzite is not a mineral.


Question: Which solution has a higher concentration of blue particles?

Choices:
- neither; their concentrations are the same
- Solution B
- Solution A

The diagram below is a model of two solutions. Each blue ball represents one particle of solute.

natural science

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

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


Question: Which of these cities is marked on the map?

Choices:
- Oklahoma City
- Nashville
- New Orleans
- Miami

social science

Solution: The city is Miami, Florida. Oklahoma City, New Orleans, and Nashville are marked with gray circles on the map below.


Question: What is the name of the colony shown?

Choices:
- Tennessee
- Virginia
- Maryland
- West Virginia

social science

Solution:
The colony is Virginia.
The Virginia Colony included land that would later become part of the state of West Virginia. West Virginia was never its own colony.


Question: What can Gordon and Ariel trade to each get what they want?

Choices:
- Ariel can trade her broccoli for Gordon's oranges.
- Gordon can trade his tomatoes for Ariel's carrots.
- Ariel can trade her almonds for Gordon's tomatoes.
- Gordon can trade his tomatoes for Ariel's broccoli.

Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another.
Gordon and Ariel open their lunch boxes in the school cafeteria. Neither Gordon nor Ariel got everything that they wanted. The table below shows which items they each wanted:

Look at the images of their lunches. Then answer the question below.
Gordon's lunch Ariel's lunch

social science

Solution:
Look at the table and images.
Gordon wants broccoli. Ariel wants tomatoes. They can trade tomatoes for broccoli to both get what they want. Trading other things would not help both people get more items they want.


Question: Is Polytrichum commune made up of one cell?

Choices:
- yes
- no

This organism is Polytrichum commune. It is a member of the plant kingdom.
Polytrichum commune is also called the common haircap moss. This plant gets its common name from its brown, cap-like structures. Those structures contain spores. After the spores are released, they can settle on the ground and grow into new mosses.

natural science

Describe, classify, and compare kingdoms

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

Solution: Polytrichum commune is a plant. Plants are made up of many cells.


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

Choices:
- The magnitude of the magnetic force is greater in Pair 1.
- The magnitude of the magnetic force is the same in both pairs.
- The magnitude of the magnetic force is greater in Pair 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, but some of them are different sizes and shapes.

natural science

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

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


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

Choices:
- The magnetic force is stronger in Pair 1.
- The strength of the magnetic force is the same in both pairs.
- The magnetic force is stronger in Pair 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.

natural science

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

Solution:
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.


Question: Which of the following could Shelley's test show?

Choices:
- how much the drone weighed with the blade guards
- if adding the blade guards made the drone fly poorly
- if the blade guards would break in a crash

People can use the engineering-design process to develop solutions to problems. One step in the process is testing if a potential solution meets the requirements of the design.
The passage below describes how the engineering-design process was used to test a solution to a problem. Read the passage. Then answer the question below.

Shelley was designing small aircraft called drones to pick up items from warehouse shelves. She knew that the drones' propeller blades would get damaged if they bumped into anything while flying through the warehouse. So, Shelley wanted to add blade guards to protect the propeller blades. The guards had to be sturdy so they would not break in a crash. But she thought that if the guards weighed too much, the drones would not fly well.
So, Shelley put guards made of lightweight metal on one drone. Then she observed how well the drone flew with the guards.
Figure: a drone without blade guards.

natural science

Evaluate tests of engineering-design solutions

People can use the engineering-design process to develop solutions to problems. One step in the process is testing if a potential solution meets the requirements of the design. How can you determine what a test can show? You need to figure out what was tested and what was measured.
Imagine an engineer needs to design a bridge for a windy location. She wants to make sure the bridge will not move too much in high wind. So, she builds a smaller prototype, or model, of a bridge. Then, she exposes the prototype to high winds and measures how much the bridge moves.
First, identify what was tested. A test can examine one design, or it may compare multiple prototypes to each other. In the test described above, the engineer tested a prototype of a bridge in high wind.
Then, identify what the test measured. One of the criteria for the bridge was that it not move too much in high winds. The test measured how much the prototype bridge moved.
Tests can show how well one or more designs meet the criteria. The test described above can show whether the bridge would move too much in high winds.


Question: Which continent is highlighted?

Choices:
- Africa
- Asia
- South America
- Antarctica

social science

A continent is one of the major land masses on the earth. Most people say there are seven continents.

Solution: This continent is Africa.


Question: What is the capital of Connecticut?

Choices:
- Bridgeport
- Albany
- Hartford
- New Haven

social science

Identify state capitals of the Northeast

Solution: Hartford is the capital of Connecticut.


Question: Based on clues in the text, why would farmers have appreciated cats eight thousand years ago?

Choices:
- The cats were thought to be visiting goddesses.
- The cats hunted and brought food to the farmers.
- The cats helped keep the farmers' grain free of mice.
- The cats helped farmers find better places to store grain.

Read the text about cats.
Cats are among the most popular pets in the world. Millions of people have welcomed cats into their homes. Indeed, researchers believe that the relationship between cats and humans goes back to prehistoric times. But throughout history, different cultures and people around the world have had different sentiments about cats. Such feelings have ranged from fear to worship.
People probably first developed friendly relationships with cats around eight thousand years ago, when farming and agriculture had just started to develop in the Middle East. Farmers were growing and storing grain, which in turn attracted mice and other pests. Cats were wild then. However, they were likely drawn to farming communities because there were mice to hunt. The farmers would have noticed and appreciated these visitors. To keep the cats around, these early farmers may have given food and even shelter to the wild cats. The farmers and cats probably helped one another.
It wasn't until five thousand years later that the Egyptians started to treat cats as pets. Cats in ancient Egypt were not simply valued, but considered sacred. In paintings, many Egyptian goddesses took the form of cats. People who were caught harming cats were punished severely. Some cats were even made into mummies when they died. Normally, only the richest and most powerful people were buried this way.
Later in history, some societies thought of the cat as evil. In Europe during the Middle Ages, black cats were especially feared. Some believed that witches turned themselves into black cats at night. The connection between witches and black cats lasted for many years. The idea traveled from Europe to North America as Europeans settled there. However, today cats of all colors are beloved by millions of people worldwide. In fact, the way some house cats are treated now might make their Egyptian ancestors jealous!

language science

Informational texts include many facts, examples, and details. Authors don't always directly state how these things connect to each other. So, you may need to make guesses, or inferences, to understand how the ideas from the text fit together. Inferences can help you understand the whole text and draw conclusions about the information. Be sure to base your inferences on details found in the text as well as things you already know.

Solution:
Think about these details from the text:
Grain attracted mice and other pests.
Cats were drawn to farms to hunt mice.
You may know that mice like to eat grain, and that this is a problem for farmers. If cats hunted the mice, that would help stop the mice from eating the grain.
Based on these clues, you can guess that farmers appreciated cats eight thousand years ago because the cats helped keep their grain free of mice.


Question: What is the capital of Missouri?

Choices:
- Pierre
- Kansas City
- Jefferson City
- Wichita

social science

Solution: Jefferson City is the capital of Missouri.


Question: Which property do these four objects have in common?

Choices:
- salty
- rough
- flexible

natural science

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

Solution:
Look at each object.
For each object, decide if it has that property.
A rough object feels scratchy when you touch it. All four objects are rough.
Potato chips have a salty taste. The pineapple is not salty.
A flexible object can be folded or bent without breaking easily. The potato sack is flexible, but the rock and the sidewalk are not.
The property that all four objects have in common is rough.


Question: Which property do these three objects have in common?

Choices:
- translucent
- stretchy
- bumpy

natural science

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

Solution:
Look at each object.
For each object, decide if it has that property.
A bumpy object is covered in lumps and bumps. The honey is not bumpy.
A stretchy object gets longer when you pull on it. The wet ice cube is not stretchy.
A translucent object lets light through. But you cannot see clearly through a translucent object. All three objects are translucent.
The property that all three objects have in common is translucent.


Question: Identify the question that Gwen's experiment can best answer.

Choices:
- Do circuits that include iron produce dimmer light than circuits that include copper?
- Can light bulbs stay lit longer when circuits include copper or when circuits include iron?

The passage below describes an experiment. Read the passage and then follow the instructions below.

Gwen built an electric circuit: she used wires to connect a battery to a light bulb, the light bulb to a small piece of copper, and the copper back to the battery. When the circuit was complete, the light turned on. Gwen observed the brightness of the light for five seconds. She then replaced the copper with a piece of iron of equal size and noted whether the light became brighter or dimmer. Gwen built three more of the same type of circuit. She repeated the tests with each circuit. Gwen recorded whether the circuits produced brighter light when the circuit included copper or when the circuit included iron.
Figure: a circuit with a battery, a light bulb, and a piece of copper.

natural science

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?


Question: Which trait did Galeocerdo have? Select the trait you can observe on the fossil.

Choices:
- a round, flat body
- fins on its back
- gray skin

This picture shows a fossil of an animal called Galeocerdo.
Some fossils of Galeocerdo are over 2,000,000 years old.

natural science

The way an organism looks or acts is called a trait. Scientists use fossils to learn more about the traits of ancient organisms.
Fossils can preserve the remains of body parts and activities. A fossil of a body part, such as a tail or a wing, can tell you what an organism looked like. A fossil of an organism's activities, such as a burrow or a footprint, can tell you about the organism's behavior.
Here are three examples of fossils and the traits that you can observe from them:
This is a fossil of an animal. This fossil tells you that the animal had a spiral-shaped shell.
This is a fossil of a plant. This fossil tells you that the plant had small leaves arranged in a branched pattern.
This is a fossil of an animal's footprint. This fossil tells you that the animal could walk on land.
An organism's fossil may not show all of the organism's traits. This is because most body parts are destroyed during fossil formation. When an organism's body turns into a fossil, only a few body parts are usually preserved.


Question: Which material is this clothes hanger made of?

Choices:
- metal
- wool

natural science

A material is a type of matter. Wood, glass, metal, and plastic are common materials.
Some objects are made of just one material.
Most nails are made of metal.
Other objects are made of more than one material.
This hammer is made of metal and wood.

Solution:
Look at the picture of the clothes hanger.
The clothes hanger is made of two different materials. The hook is made of metal. The rest of the hanger is made of wood.


Question:
Complete the statement.
Nickel is ().

Choices:
- an elementary substance
- a compound

The model below represents nickel. ckel is a metal that is used in coins and in rechargeable batteries.

natural science

Classify elementary substances and compounds using models

There are more than 100 different chemical elements, or types of atoms. Chemical elements make up all of the substances around you.
A substance may be composed of one chemical element or multiple chemical elements. Substances that are composed of only one chemical element are elementary substances. Substances that are composed of multiple chemical elements bonded together are compounds.
Every chemical element is represented by its own atomic symbol. An atomic symbol may consist of one capital letter, or it may consist of a capital letter followed by a lowercase letter. For example, the atomic symbol for the chemical element fluorine is F, and the atomic symbol for the chemical element beryllium is Be.
Scientists use different types of models to represent substances whose atoms are bonded in different ways. One type of model is a space-filling model. The space-filling model below represents the elementary substance copper.
In a space-filling model, the balls represent atoms that are bonded together. The color of a ball represents a specific chemical element. The atomic symbol for that chemical element is shown in the legend.

Solution:
Use the model to determine whether nickel is an elementary substance or a compound.
Step 1: Interpret the model.
In the space-filling model shown above, all of the balls are the same color:
. The legend shows that dark blue represents the chemical element with the atomic symbol Ni. So, the model shows you that nickel is composed of one chemical element.
Step 2: Determine whether the substance is an elementary substance or a compound.
You know from Step 1 that nickel is composed of only one chemical element. So, nickel is an elementary substance.


Question: Based on the Venn diagram, what do the Odyssey and the Aeneid have in common?

Choices:
- They are both set after the Trojan War.
- They were both written by Virgil.

language science

A graphic organizer is a chart or picture that shows how ideas, facts, or topics are related to one another.
When you read, look for graphic organizers included in the text. You can use these images to find key information. You can also create your own graphic organizers with information that you've read. Doing this can help you think about the ideas in the text and easily review them.
When you write, you can use graphic organizers to organize your thoughts and plan your writing.

Solution:
In a Venn diagram, each circle shows information that is true for a particular topic. In any area where circles overlap, the information is true for all of the overlapping topics. This Venn diagram shows information about two ancient poems.
Set after the Trojan War appears in both the circle for the Odyssey and the circle for the Aeneid. This tells you that the Odyssey and the Aeneid are both set after the Trojan War.


Question: Which animal's feet are also adapted for walking on large, floating leaves?

Choices:
- Magellan penguin
- purple gallinule

Bronze-winged jacanas live near rivers and lakes. They eat insects and snails that live on plants floating on the surface of the water.
The feet of the jacana are adapted for walking on large, floating leaves. The jacana uses its feet to spread its weight out over a wide area. This helps the bird walk on the leaves without sinking into the water.
Figure: bronze-winged jacana.

natural science

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors.
The shape of an animal's 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.

Solution:
Look at the picture of the bronze-winged jacana.
The bronze-winged jacana uses its toes to spread its weight out over a large area. This can help it walk on leaves without sinking into the water.
Now look at each animal. Figure out which animal has a similar adaptation.
The purple gallinule has long, thin toes on its feet. Its feet are adapted for walking on floating leaves.
The Magellan penguin has webbed feet. Its feet are not adapted for walking on floating leaves. The Magellan penguin uses its feet to walk and swim.


Question: Which trait did Diplomystus have? Select the trait you can observe on the fossil.

Choices:
- reddish-orange scales on its body
- a V-shaped tail fin

This picture shows a fossil of an ancient fish called Diplomystus. Diplomystus lived in ancient lakes and ate smaller fish.

natural science

The way an organism looks or acts is called a trait. Scientists use fossils to learn more about the traits of ancient organisms.
Fossils can preserve the remains of body parts and activities. A fossil of a body part, such as a tail or a wing, can tell you what an organism looked like. A fossil of an organism's activities, such as a burrow or a footprint, can tell you about the organism's behavior.
Here are three examples of fossils and the traits that you can observe from them:
This is a fossil of an animal. This fossil tells you that the animal had a spiral-shaped shell.
This is a fossil of a plant. This fossil tells you that the plant had small leaves arranged in a branched pattern.
This is a fossil of an animal's footprint. This fossil tells you that the animal could walk on land.
An organism's fossil may not show all of the organism's traits. This is because most body parts are destroyed during fossil formation. When an organism's body turns into a fossil, only a few body parts are usually preserved.


Question: Which property do these four objects have in common?

Choices:
- sticky
- hard
- stretchy

natural science

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

Solution:
Look at each object.
For each object, decide if it has that property.
A stretchy object gets longer when you pull on it. The bubble gum is stretchy, but the ice pop and the chocolate milkshake are not.
A sticky object can attach or stick to other things. All four objects are sticky.
A hard object does not change shape when pressed or squeezed. The ice pop is hard, but the cake batter, the chocolate milkshake, and the bubble gum are not.
The property that all four objects have in common is sticky.


Question: Which statement best describes the average monthly precipitation in Boston?

Choices:
- March is the month with the highest average precipitation.
- About the same amount of precipitation falls each month between May and October.
- Precipitation does not change much from month to month in Boston.

Use the graph to answer the question below.

natural science

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

Solution:
To describe the average precipitation trends in Boston, look at the graph.
Choice "Mar" is incorrect.
Choice "May" is incorrect.
Choice "Oct" is incorrect.
Choice "Precipitation does not change much from month to month in Boston." is incorrect.
On average, more precipitation falls between November and April than between May and October.
Choice "About the same amount of precipitation falls each month between May and October." is incorrect.
The average precipitation each month between May and October is about 3 inches. So, about the same amount of precipitation falls during each of these months.
Choice "March is the month with the highest average precipitation." is incorrect.
January, not March, has the highest average monthly precipitation.


Question: Will these magnets attract or repel each other?

Choices:
- repel
- attract

natural science

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

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


Question: Which animal's feet are also adapted for walking on large, floating leaves?

Choices:
- emu
- northern jacana

Bronze-winged jacanas live near rivers and lakes. They eat insects and snails that live on plants floating on the surface of the water.
The feet of the jacana are adapted for walking on large, floating leaves. The jacana uses its feet to spread its weight out over a wide area. This helps the bird walk on the leaves without sinking into the water.
Figure: bronze-winged jacana.

natural science

An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors.
The shape of an animal's 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.

Solution:
Look at the picture of the bronze-winged jacana.
The bronze-winged jacana uses its toes to spread its weight out over a large area. This can help it walk on leaves without sinking into the water.
Now look at each animal. Figure out which animal has a similar adaptation.
The northern jacana has long, thin toes on its feet. Its feet are adapted for walking on floating leaves.
The emu has large, heavy feet with thick toes. Its feet are not adapted for walking on floating leaves. The emu uses its feet to walk and run on hard ground.


Question: Which trait did Coelodonta have? Select the trait you can observe on the fossil.

Choices:
- a black snout
- a tail

This picture shows a fossil of an ancient animal called Coelodonta.
Coelodonta was hunted by early humans and went extinct about 10,000 years ago.

natural science

The way an organism looks or acts is called a trait. Scientists use fossils to learn more about the traits of ancient organisms.
Fossils can preserve the remains of body parts and activities. A fossil of a body part, such as a tail or a wing, can tell you what an organism looked like. A fossil of an organism's activities, such as a burrow or a footprint, can tell you about the organism's behavior.
Here are three examples of fossils and the traits that you can observe from them:
This is a fossil of an animal. This fossil tells you that the animal had a spiral-shaped shell.
This is a fossil of a plant. This fossil tells you that the plant had small leaves arranged in a branched pattern.
This is a fossil of an animal's footprint. This fossil tells you that the animal could walk on land.
An organism's fossil may not show all of the organism's traits. This is because most body parts are destroyed during fossil formation. When an organism's body turns into a fossil, only a few body parts are usually preserved.


Question: Which country is highlighted?

Choices:
- Haiti
- Saint Lucia
- Barbados
- Saint Vincent and the Grenadines

social science

Identify and select countries of the Caribbean

Solution: This country is Saint Lucia.


Question: Which statement describes the Yasuni National Park ecosystem?

Choices:
- It has mostly small plants.
- It has soil that is poor in nutrients.
- It has soil that is rich in nutrients.

Figure: Yasuni National Park.
The Amazon rain forest in South America is the largest rain forest ecosystem in the world. Ecuador's Yasuni National Park, which is in the Amazon rain forest, has many different species of plants, birds, and mammals.

natural science

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

Solution: 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, the following statement describes the Yasuni National Park ecosystem: year-round rain and warm temperatures, soil that is poor in nutrients, and many different types of organisms. It has soil that is poor in nutrients. The following statements do not describe Yasuni National Park: year-round rain and warm temperatures, soil that is poor in nutrients, and many different types of organisms. It has soil that is rich in nutrients. It has mostly small plants.


Question: Which statement best describes the average monthly precipitation in New Orleans?

Choices:
- The wettest months of the year are June, July, and August.
- October is the wettest month.
- June, July, and August are the driest months of the year.

Use the graph to answer the question below.

natural science

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

Solution:
To describe the average precipitation trends in New Orleans, look at the graph.
Choice "Jun" is incorrect.
Choice "Jul" is incorrect.
Choice "Aug" is incorrect.
Choice "Oct" is incorrect.
Choice "June, July, and August are the driest months of the year." is incorrect.
On average, slightly more precipitation falls during June, July, and August than during the other months of the year. So, June, July, and August are not the driest months.
Choice "The wettest months of the year are June, July, and August." is incorrect.
On average, more precipitation falls during June, July, and August than during other months of the year. So, June, July, and August are the wettest months.
Choice "October is the wettest month." is incorrect.
Every other month has a higher average precipitation than October. So, October is the driest, not the wettest, month.


Question: Which material is this dress made of?

Choices:
- glass
- cotton

natural science

A material is a type of matter. Wood, glass, metal, and plastic are common materials.

Solution:
Look at the picture of the dress.
This dress is made of cotton.
Not all dresses are made of cotton. Dresses can be made from silk, wool, linen, or many other fabrics.


Question: What is the capital of Hawaii?

Choices:
- Honolulu
- Little Rock
- Hilo
- Jefferson City

social science

Solution: Honolulu is the capital of Hawaii.


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

Choices:
- sample A
- sample B
- neither; the samples have the same temperature

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.

natural science

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.

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


Question:
Is the following statement about our solar system true or false?
Jupiter's volume is more than 10,000 times as large as the volume of Mars.

Choices:
- true
- false

Use the data to answer the question below.

natural science

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

Solution:
To determine if this statement is true, calculate the value of 10,000 times the volume of Mars.
Then compare the result to the volume of Jupiter. Jupiter's volume is 1.43 x 10^15 km^3, which is less than 1.63 x 10^15 km^3. So, Jupiter's volume is less than 10,000 times as large as the volume of Mars.