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

Choices:
- Do radish plants grown under bright light have more leaves than radish plants grown under dim light?
- Do radishes grown under bright light get bigger than radishes grown under dim light?

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

Annie planted 20 radish plants in a greenhouse, putting each plant in its own pot. She placed ten of the pots under bright light and the other ten pots under dim light. Annie watered all the plants twice a day. After two months, she pulled the radish plants from the ground, threw away the leafy green tops, and measured the sizes of the radishes. She compared the sizes of the radishes grown under bright light to the sizes of the radishes grown under dim light.
Figure: a radish plant in soil.

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

The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.

natural science

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

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


Question: Which country is highlighted?

Choices:
- Fiji
- Solomon Islands
- Vanuatu
- Tuvalu

social science

Identify and select countries of Oceania

Solution: This country is Fiji.


Question: What is the capital of Wyoming?

Choices:
- Hilo
- Laramie
- Carson City
- Cheyenne

social science

Solution: Cheyenne is the capital of Wyoming.


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

Choices:
- Pittsburgh
- Baltimore
- New York City
- Boston

social science

Solution: The city is New York City, New York. Pittsburgh, Boston, and Baltimore are marked with gray circles on the map below.


Question: What can Sally and Chloe trade to each get what they want?

Choices:
- Sally can trade her tomatoes for Chloe's sandwich.
- Chloe can trade her almonds for Sally's tomatoes.
- Chloe can trade her broccoli for Sally's oranges.
- Sally can trade her tomatoes for Chloe'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.
Sally and Chloe open their lunch boxes in the school cafeteria. Both of them could be happier with their lunches. Sally wanted broccoli in her lunch and Chloe was hoping for tomatoes. Look at the images of their lunches. Then answer the question below.

social science

Solution:
Sally wanted broccoli in her lunch and Chloe was hoping for tomatoes. Look at the labeled part of the images.
Sally has tomatoes. Chloe 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 Nevada?

Choices:
- Carson City
- Reno
- Salem
- Las Vegas

social science

Solution: Carson City is the capital of Nevada.


Question: Does this passage describe the weather or the climate?

Choices:
- weather
- climate

Figure: Istanbul.
Istanbul is on the coast of Turkey, where nighttime temperatures average between 60°F and 70°F each year during June, July, and August.
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.

natural science

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

Solution:
Read the passage carefully.
Istanbul is on the coast of Turkey, where nighttime temperatures average between 60°F and 70°F each year during June, July, and August.
This passage tells you about the usual temperature pattern in Istanbul. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.


Question: Select the organism in the same species as the marbled salamander.

Choices:
- Lissotriton helveticus
- Taricha torosa
- Ambystoma opacum

This organism is a marbled salamander. Its scientific name is Ambystoma opacum.

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 marbled salamander's scientific name is Ambystoma opacum.
Taricha torosa does not have the same scientific name as a marbled salamander. So, Ambystoma opacum and Taricha torosa are not in the same species.
Ambystoma opacum has the same scientific name as a marbled salamander. So, these organisms are in the same species.
Lissotriton helveticus does not have the same scientific name as a marbled salamander. So, Ambystoma opacum and Lissotriton helveticus are not in the same species.


Question: Select the amphibian below.

Choices:
- human
- red-spotted newt
- great white shark
- gray wolf

Amphibians have moist skin and begin their lives in water.
Amphibians are cold-blooded. The body temperature of cold-blooded animals depends on their environment.
A gray tree frog 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. Scientists sort animals into each group based on traits they have in common. This process is called classification.
Classification helps scientists learn about how animals live. Classification also helps scientists compare similar animals.

Solution:
A human is a mammal. It has hair and feeds its young milk.
Humans are a type of animal called a primate. Monkeys and apes are also primates.
A gray wolf is a mammal. It has fur and feeds its young milk.
Wolves often live in family groups. A wolf mother, father, and their children travel together.
A great white shark is a fish. It lives underwater. It has fins, not limbs.
Great white sharks can live for up to 70 years.
A red-spotted newt is an amphibian. It has moist skin and begins its life in water.
Some newts live in water. Other newts live on land but lay their eggs in water.


Question: Will these magnets attract or repel each other?

Choices:
- repel
- attract

Two magnets are placed as shown.

Hint: Magnets that attract pull together. Magnets that repel push apart.

natural science

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

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


Question: Select the reptile below.

Choices:
- koala
- box turtle

Reptiles have scaly, waterproof skin. Most reptiles live on land. A helmeted iguana is an example of a reptile.

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 box turtle is a reptile. It has scaly, waterproof skin.


Question: What is the capital of New Hampshire?

Choices:
- Manchester
- Nampa
- Concord
- Grand Rapids

social science

Identify state capitals of the Northeast

Solution: Concord is the capital of New Hampshire.


Question: Which property matches this object?

Choices:
- blue
- shiny

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 shiny object reflects a lot of light. The trombone is shiny.
Blue is a color.
This color is blue. The trombone is not blue.


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

Choices:
- The strength of the magnetic force is the same in both pairs.
- The magnetic force is stronger in Pair 1.
- 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.
You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is stronger when the magnets are closer together.

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


Question: What is the capital of California?

Choices:
- Birmingham
- Charleston
- Sacramento
- Richmond

social science

Solution: Sacramento is the capital of California.


Question: Does this passage describe the weather or the climate?

Choices:
- climate
- weather

Figure: Nicaragua.
Winds are called offshore when they blow from land to water. The winds in southern Nicaragua blow offshore over 300 days per year. Most people prefer to surf on days when the winds are offshore.
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.

natural science

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

Solution:
Read the passage carefully.
Winds are called offshore when they blow from land to water. The winds in southern Nicaragua blow offshore over 300 days per year. Most people prefer to surf on days when the winds are offshore.
The underlined part of the passage tells you about the usual wind patterns in Nicaragua. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.


Question: What is the capital of Maine?

Choices:
- Augusta
- Phoenix
- Portland
- Madison

social science

Identify state capitals of the Northeast

Solution: Augusta is the capital of Maine.


Question: What is the capital of Iowa?

Choices:
- Cedar Rapids
- Davenport
- Des Moines
- Frankfort

social science

Solution: Des Moines is the capital of Iowa.


Question: What is the capital of Indiana?

Choices:
- Pierre
- Springfield
- Fort Wayne
- Indianapolis

social science

Solution: Indianapolis is the capital of Indiana.


Question: Select the fish below.

Choices:
- mandarinfish
- green iguana
- red-headed poison frog
- water buffalo

Fish live underwater. They have fins, not limbs.
Fish are cold-blooded. The body temperature of cold-blooded animals depends on their environment.
A salmon is an example of a fish.

natural science

Identify mammals, birds, fish, reptiles, and amphibians

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

Solution:
A green iguana is a reptile. It has scaly, waterproof skin.
Iguanas are a type of lizard. Iguanas eat plants and fruit.
A water buffalo is a mammal. It has hair and feeds its young milk.
Water buffaloes live in Asia. Some people raise water buffaloes for their milk.
A red-headed poison frog is an amphibian. It has moist skin and begins its life in water.
Poison dart frogs come in many bright colors. Their bright color warns other animals that these frogs are poisonous.
A mandarinfish is a fish. It lives underwater. It has fins, not limbs.
Mandarinfish often live near coral reefs. They eat small worms, snails, and fish eggs.


Question: Select the organism in the same genus as the bobcat.

Choices:
- Lynx canadensis
- Python molurus
- Macropus rufus

This organism is a bobcat. Its scientific name is Lynx rufus.

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 bobcat's scientific name is Lynx rufus. The first word of its scientific name is Lynx.
Lynx canadensis is in the genus Lynx. The first word of its scientific name is Lynx. So, Lynx canadensis and Lynx rufus are in the same genus.
Macropus rufus and Lynx rufus are not in the same genus.
These organisms are not in the same genus, but part of their scientific names is the same. Macropus rufus and Lynx rufus have the same species name within their genus, rufus. But the first words of their scientific names are different. Macropus rufus is in the genus Macropus, and Lynx rufus is in the genus Lynx.
Python molurus is in the genus Python. The first word of its scientific name is Python. So, Python molurus and Lynx rufus are not in the same genus.


Question: Which i in row B?

Choices:
- the fire department
- the police department
- the library
- the diner

social science

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

Solution: The library is in row B.


Question: Which better describes the Everglades National Park ecosystem?

Choices:
- It has land that is covered in water during most of the year. It also has other water ecosystems nearby.
- It has soil that is poor in nutrients. It also has other water ecosystems nearby.

Figure: Everglades National Park.
Everglades National Park is a wetland ecosystem in southern Florida.

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 wetland is a type of ecosystem. Wetlands have the following features: land that is covered with water during most of the year, soil that is rich in nutrients, and other water ecosystems nearby. So, Everglades National Park has land that is covered with water during most of the year. It also has other water ecosystems nearby.


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: What type of rock is shale?

Choices:
- sedimentary
- igneous

Shale is a type of rock. It forms when layers of mud are pressed together to form rock. Shale is often found near underground deposits of fossil fuels such as oil.

natural science

Classify rocks as igneous, sedimentary, or metamorphic

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

Solution:
Shale is a sedimentary rock. Like other sedimentary rocks, it forms from layers of sediment.
Mud is a type of sediment. It is found in places like lakes and oceans. Sediments like mud usually build up in layers. Over time, the top layers press down on the bottom layers. Sedimentary rock can form when the bottom layers are pressed together to form rock.


Question:
Complete the text to describe the diagram.
Solute particles moved in both directions across the permeable membrane. But more solute particles moved across the membrane (). When there was an equal concentration on both sides, the particles reached equilibrium.

Choices:
- to the left than to the right
- to the right than to the left

The diagram below shows a solution with one solute. Each solute particle is represented by a purple ball. The solution fills a closed container that is divided in half by a membrane. The membrane, represented by a dotted line, is permeable to the solute particles.
The diagram shows how the solution can change over time during the process of diffusion.

natural science

In a solution, solute particles move and spread throughout the solvent. The diagram below shows how a solution can change over time. Solute particles move from the area where they are at a higher concentration to the area where they are at a lower concentration. This movement happens through the process of diffusion.
As a result of diffusion, the concentration of solute particles becomes equal throughout the solution. When this happens, the solute particles reach equilibrium. At equilibrium, the solute particles do not stop moving. But their concentration throughout the solution stays the same.
Membranes, or thin boundaries, can divide solutions into parts. A membrane is permeable to a solute when particles of the solute can pass through gaps in the membrane. In this case, solute particles can move freely across the membrane from one side to the other.
So, for the solute particles to reach equilibrium, more particles will move across a permeable membrane from the side with a higher concentration of solute particles to the side with a lower concentration. At equilibrium, the concentration on both sides of the membrane is equal.

Solution:
Look at the diagram again. It shows you how the solution changed during the process of diffusion.
Before the solute particles reached equilibrium, there were 4 solute particles on the left side of the membrane and 6 solute particles on the right side of the membrane.
When the solute particles reached equilibrium, there were 5 solute particles on each side of the membrane. There was 1 more solute particle on the left side of the membrane than before.
So, for the solute particles to reach equilibrium, more solute particles must have moved across the membrane to the left than to the right.


Question: Does this passage describe the weather or the climate?

Choices:
- weather
- climate

Figure: Des Moines.
Des Moines has cold winters and warm summers.
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.

natural science

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

Solution:
Read the passage carefully.
Des Moines has cold winters and warm summers.
This passage tells you about the usual temperature pattern in Des Moines. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.


Question: What is the capital of Illinois?

Choices:
- Chicago
- Columbus
- Springfield
- Jefferson City

social science

Solution: Springfield is the capital of Illinois.


Question: Which is this organism's common name?

Choices:
- Bradypus variegatus
- brown-throated sloth

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, it is the scientific name.
Bradypus variegatus is the organism's scientific name. So, you know that brown-throated sloth is the common name.


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

Choices:
- which design would have the greatest distance between the concert area and the road
- if at least 20% of the park would be shaded by trees in each design
- which design would have the least traffic noise in the concert area

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.

Isaac was a landscape architect who was hired to design a new city park. The city council wanted the park to have space for outdoor concerts and to have at least 20% of the park shaded by trees. Isaac thought the concert area should be at least 150 meters from the road so traffic noise didn't interrupt the music. He developed three possible designs for the park with the concert area in a different location in each design. Then, he tested each design by measuring the distance between the road and the concert area.
Figure: studying an architect's design.

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 property do these two objects have in common?

Choices:
- sour
- stretchy

natural science

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

Solution:
Look at each object.
For each object, decide if it has that property.
A stretchy object gets longer when you pull on it. Both objects are stretchy.
A lemon has a sour taste. The balloon is not sour.
The property that both objects have in common is stretchy.


Question: What is this huntsman spider's scientific name?

Choices:
- Heteropoda davidbowie
- Heteropoda altmannae

This species of huntsman spider was discovered in Malaysia in 2008. It was named in honor of the musician David Bowie.

natural science

When a scientist identifies a new organism, he or she chooses its scientific name.
Sometimes, an organism is named after the place where it was first found. Other times, an organism is named after the scientist who first identified it. Or, the scientific name might describe the organism's physical traits.
Many of the words that make up scientific names are based on words from old languages, like Latin and classical Greek. Sometimes, English words are changed to make them sound more like Latin or Greek. The new words are then used in an organism's scientific name.

Solution:
This organism's scientific name refers to David Bowie.
The word davidbowie refers to David Bowie. So, this huntsman spider's scientific name is Heteropoda davidbowie.


Question: What is the expected ratio of offspring with a yellow ground spot to offspring with a white ground spot? Choose the most likely ratio.

Choices:
- 4:0
- 3:1
- 1:3
- 0:4
- 2:2

This passage describes the ground spot color trait in watermelon plants:
Watermelon plants grow with their fruit resting on the ground. Over time, the bottom of each fruit develops a white or yellow spot called a ground spot. In some types of watermelon plants, the color of the ground spot is an inherited trait.
In a group of watermelon plants, some individuals have a yellow ground spot and others have a white ground spot. In this group, the gene for the ground spot color trait has two alleles. The allele for a white ground spot (g) is recessive to the allele for a yellow ground spot (G).
This Punnett square shows a cross between two watermelon plants.

natural science

Use Punnett squares to calculate ratios of offspring types

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

Solution:
To determine how many boxes in the Punnett square represent offspring with a yellow ground spot or a white ground spot, consider whether each phenotype is the dominant or recessive allele's version of the ground spot color trait. The question tells you that the g allele, which is for a white ground spot, is recessive to the G allele, which is for a yellow ground spot.
A yellow ground spot is the dominant allele's version of the ground spot color trait. A watermelon plant with the dominant version of the ground spot color trait must have at least one dominant allele for the ground spot color gene. So, offspring with a yellow ground spot must have the genotype GG or Gg.
All 4 boxes in the Punnett square have the genotype GG or Gg.
A white ground spot is the recessive allele's version of the ground spot color trait. A watermelon plant with the recessive version of the ground spot color trait must have only recessive alleles for the ground spot color gene. So, offspring with a white ground spot must have the genotype gg.
There are 0 boxes in the Punnett square with the genotype gg.
So, the expected ratio of offspring with a yellow ground spot to offspring with a white ground spot is 4:0. This means that, based on the Punnett square, this cross will always produce offspring with a yellow ground spot. This cross is expected to never produce offspring with a white ground spot.


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

Choices:
- four legs
- a tail with long hair
- a mane on the back of its neck

This picture shows a fossil of an ancient animal called Megaloceros. An adult Megaloceros could grow over seven feet tall.

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 egg carton made of?

Choices:
- ceramic
- cardboard

natural science

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

Solution:
Look at the picture of the egg carton.
The egg carton is made of cardboard.
Not all egg cartons are made of cardboard. Some egg cartons are made of plastic, or even styrofoam.


Question: Which animal is also adapted to be camouflaged in the snow?

Choices:
- echidna
- Arctic fox

Ptarmigans live in cold, snowy places. The  is adapted to be camouflaged in the snow.
Figure: ptarmigan.

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 ptarmigan.
During the winter, the ptarmigan has white feathers covering its body. It is adapted to be camouflaged in the snow. The word camouflage means to blend in.
Now look at each animal. Figure out which animal has a similar adaptation.
During the winter, the Arctic fox has white fur covering its body. It is adapted to be camouflaged in the snow.
The echidna has a yellow and brown body. It is not adapted to be camouflaged in the snow.


Question: What is the name of the colony shown?

Choices:
- New Jersey
- Delaware
- Maine
- Pennsylvania

social science

Solution: The colony is New Jersey.


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

Choices:
- rough
- smooth
- soft

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 smooth object is not scratchy or rough. All three objects are smooth.
A rough object feels scratchy when you touch it. None of the objects are rough.
A soft object changes shape when pressed or squeezed. None of the objects are soft.
The property that all three objects have in common is smooth.


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 1 than in Pair 2. So, the magnitude of the magnetic force is greater in Pair 1 than in Pair 2.


Question: Select the organism in the same genus as the great blue heron.

Choices:
- Strix varia
- Pelecanus crispus
- Ardea purpurea

This organism is a great blue heron. Its scientific name is Ardea herodias.

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 great blue heron's scientific name is Ardea herodias. The first word of its scientific name is Ardea.
Strix varia is in the genus Strix. The first word of its scientific name is Strix. So, Strix varia and Ardea herodias are not in the same genus.
Pelecanus crispus is in the genus Pelecanus. The first word of its scientific name is Pelecanus. So, Pelecanus crispus and Ardea herodias are not in the same genus.
Ardea purpurea is in the genus Ardea. The first word of its scientific name is Ardea. So, Ardea purpurea and Ardea herodias are in the same genus.


Question: What can Rosa and Isabella trade to each get what they want?

Choices:
- Isabella can trade her broccoli for Rosa's oranges.
- Rosa can trade her tomatoes for Isabella's broccoli.
- Rosa can trade her tomatoes for Isabella's carrots.
- Isabella can trade her almonds for Rosa'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.
Rosa and Isabella open their lunch boxes in the school cafeteria. Neither Rosa nor Isabella 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.
Rosa's lunch Isabella's lunch

social science

Solution:
Look at the table and images.
Rosa wants broccoli. Isabella 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 Hawaii?

Choices:
- Sacramento
- Carson City
- Honolulu
- Hilo

social science

Solution: Honolulu is the capital of Hawaii.


Question: What is one reason people can't go to Mars?

Choices:
- It's too far away.
- It's too hot there.

Read the passage about the Mars robot Curiosity.
People can't make it to Mars yet. It takes too long to get there, and it's not an easy place to live. So, scientists sent a robot to look around Mars for them. The robot is named Curiosity. One of its jobs is to find out if anything can live on Mars.
Curiosity has many cameras. It takes pictures as it moves around Mars. Curiosity sends the pictures back to the scientists on Earth. Scientists hope that the pictures will make it easier for us to visit Mars someday.

language science

Read and understand informational passages

Solution:
Look at the passage. It tells you why people can't go to Mars.
People can't make it to Mars yet. It takes too long to get there, and it's not an easy place to live. So, scientists sent a robot to look around Mars for them. The robot is named Curiosity. One of its jobs is to find out if anything can live on Mars.


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

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

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.

Bill 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. Bill had to decide when the filter was too clogged and needed to be replaced. So, during his inspection, Bill 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: During this time, thermal energy was transferred from () to ().

Choices:
- the surroundings . . . each aquarium
- each aquarium . . . the surroundings

Two identical aquariums were next to an open window. One aquarium had a plastic cover on it, and the other was uncovered. This table shows how the temperature of each aquarium changed over 1.5hours.

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


Question: Which material are these steps made of?

Choices:
- concrete
- silk

natural science

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

Solution:
Look at the picture of the steps.
The steps are made of concrete.
Concrete is a mixture of sand, rocks, and cement. Concrete is heavy and strong. Bridges and large buildings are often made out of concrete.


Question: What is the capital of Idaho?

Choices:
- Boise
- Baton Rouge
- Atlanta
- Nampa

social science

Solution: Boise is the capital of Idaho.


Question: Select the organism in the same genus as the Japanese honeysuckle.

Choices:
- Hyacinthus orientalis
- Lonicera maackii
- Ulex europaeus

This organism is a Japanese honeysuckle. Its scientific name is Lonicera japonica.

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 Japanese honeysuckle's scientific name is Lonicera japonica. The first word of its scientific name is Lonicera.
Hyacinthus orientalis is in the genus Hyacinthus. The first word of its scientific name is Hyacinthus. So, Hyacinthus orientalis and Lonicera japonica are not in the same genus.
Lonicera maackii is in the genus Lonicera. The first word of its scientific name is Lonicera. So, Lonicera maackii and Lonicera japonica are in the same genus.
Ulex europaeus is in the genus Ulex. The first word of its scientific name is Ulex. So, Ulex europaeus and Lonicera japonica are not in the same genus.


Question: Which type of force from the people moves the car forward?

Choices:
- push
- pull

A car is stuck in the snow. Together, three people apply a force to the back of the car to move it forward.

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: Together, people apply a force to the back of the car to move it forward. The direction of this force is away from the people. This force is a push.


Question: Which animal's feet are also adapted to walk on snow and ice?

Choices:
- Eurasian lynx
- Suriname toad

Many s live in areas with cold, snowy winters. The 's feet are adapted for walking on snow and ice.
Figure: brown bear.

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 brown bear.
The brown bear has furry feet with large pads. Its feet are adapted to walk on snow and ice. The fur can help keep the brown bear's feet warm. The large pads help spread its weight over a larger area. This allows it to walk on ice without slipping and to walk on snow without sinking in too deep.
Now look at each animal. Figure out which animal has a similar adaptation.
The Eurasian lynx has furry feet with large pads. Its feet are adapted to walk on snow and ice.
The Suriname toad has webbed feet. Its feet are not adapted to walk on snow and ice. The Suriname toad uses its feet to swim in lakes and rivers.


Question: What is the probability that a rat produced by this cross will have a dwarf body?

Choices:
- 3/4
- 0/4
- 2/4
- 1/4
- 4/4

In a group of rats, some individuals have a normal-sized body and others have a dwarf body. In this group, the gene for the body size trait has two alleles. The allele for a dwarf body (b) is recessive to the allele for a normal-sized body (B).
This Punnett square shows a cross between two rats.

natural science

Use Punnett squares to calculate probabilities of offspring types

Offspring phenotypes: dominant or recessive?
How do you determine an organism's phenotype for a trait? Look at the combination of alleles in the organism's genotype for the gene that affects that trait. Some alleles have types called dominant and recessive. These two types can cause different versions of the trait to appear as the organism's phenotype.
If an organism's genotype has at least one dominant allele for a gene, the organism's phenotype will be the dominant allele's version of the gene's trait.
If an organism's genotype has only recessive alleles for a gene, the organism's phenotype will be the recessive allele's version of the gene's trait.
In a Punnett square, each box represents a different outcome, or result. Each of the four outcomes is equally likely to happen. Each box represents one way the parents' alleles can combine to form an offspring's genotype. Because there are four boxes in the Punnett square, there are four possible outcomes.
An event is a set of one or more outcomes. The probability of an event is a measure of how likely the event is to happen. This probability is a number between 0 and 1, and it can be written as a fraction:
probability of an event = number of ways the event can happen / number of equally likely outcomes
You can use a Punnett square to calculate the probability that a cross will produce certain offspring. For example, the Punnett square below has two boxes with the genotype Ff. It has one box with the genotype FF and one box with the genotype ff. This means there are two ways the parents' alleles can combine to form Ff. There is one way they can combine to form FF and one way they can combine to form ff.
 | F | f
F | FF | Ff
f | Ff | ff
Consider an event in which this cross produces an offspring with the genotype ff. The probability of this event is given by the following fraction:
number of ways the event can happen / number of equally likely outcomes = number of boxes with the genotype ff / total number of boxes = 1 / 4.


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

Choices:
- Australian pelican
- European robin

Common swifts eat insects and other small invertebrates. The shape of the 's beak is adapted to catch insects.
Figure: common swift.

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 a bird's beak is one example of an adaptation. Birds' beaks can be adapted in different ways. For example, a sharp hooked beak might help a bird tear through meat easily. A short, thick beak might help a bird break through a seed's hard shell. Birds that eat similar food often have similar beaks.

Solution:
Look at the picture of the common swift.
A short, thin beak is light and easy to move. The common swift uses its beak to grab fast-moving insects while flying.
Now look at each bird. Figure out which bird has a similar adaptation.
The European robin has a short, thin beak. Its beak is adapted to catch insects.
The Australian pelican has a large pouch-like beak. Its beak is not adapted to catch insects. The Australian pelican uses its beak to catch fish.


Question:
Is the following statement about our solar system true or false?
Of the four largest planets, three are made mainly of gas.

Choices:
- false
- true

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.

Solution: The table tells you that the four largest planets are Jupiter, Saturn, Uranus, and Neptune. Jupiter and Saturn are made mainly of gas. Uranus and Neptune are made mainly of ice. So, of the four largest planets, two are made mainly of gas.


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

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

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 A and Solution B have the same number of blue particles per milliliter. So, their concentrations are the same.


Question: Which animal's limbs are also adapted for climbing trees?

Choices:
- California sea lion
- lar gibbon

Three-toed sloths live in the forests of Central and South America. Their limbs are adapted for climbing trees.
Figure: three-toed sloth.

natural science

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

Solution:
Look at the picture of the three-toed sloth.
The three-toed sloth uses its long limbs to reach branches while climbing. It uses its fingers and toes to grab the branches.
Now look at each animal. Figure out which animal has a similar adaptation.
The lar gibbon has long limbs with fingers and toes. Its limbs are adapted for climbing trees.
The California sea lion has flippers. Its limbs are not adapted for climbing trees. The California sea lion uses its flippers to swim underwater.


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

Choices:
- Solution B
- neither; their concentrations are the same
- 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 A has more blue particles per milliliter. So, Solution A has a higher concentration of blue particles.


Question: Which country is highlighted?

Choices:
- Tuvalu
- Solomon Islands
- Fiji
- Vanuatu

social science

Identify and select countries of Oceania

Solution: This country is Fiji.


Question: What can Sandeep and Tracy trade to each get what they want?

Choices:
- Tracy can trade her almonds for Sandeep's tomatoes.
- Sandeep can trade his tomatoes for Tracy's broccoli.
- Sandeep can trade his tomatoes for Tracy's carrots.
- Tracy can trade her broccoli for Sandeep'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.
Sandeep and Tracy open their lunch boxes in the school cafeteria. Neither Sandeep nor Tracy 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.
Sandeep's lunch Tracy's lunch

social science

Solution:
Look at the table and images.
Sandeep wants broccoli. Tracy 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: Select the amphibian below.

Choices:
- koala
- green moray eel
- horned frog
- zebra

Amphibians have moist skin and begin their lives in water.
Amphibians are cold-blooded. The body temperature of cold-blooded animals depends on their environment.
A red-spotted newt 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. Scientists sort animals into each group based on traits they have in common. This process is called classification.
Classification helps scientists learn about how animals live. Classification also helps scientists compare similar animals.

Solution:
A koala is a mammal. It has fur and feeds its young milk.
Koalas sleep for up to 20 hours a day!
A zebra is a mammal. It has hair and feeds its young milk.
Zebras eat mostly grass. But they sometimes eat other types of plants, such as shrubs or tree bark.
A green moray eel is a fish. It lives underwater. It has fins, not limbs.
Eels are long and thin. They may have small fins. They look like snakes, but they are fish!
A horned frog is an amphibian. It has moist skin and begins its life in water.
Frogs live near water or in damp places. Most frogs lay their eggs in water.


Question: Which animal is also adapted to be camouflaged among green leaves?

Choices:
- fox snake
- emerald tree boa

Leaf insects live in the forests of Asia and Australia. The  is adapted to be camouflaged among green leaves.
Figure: leaf insect.

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 leaf insect.
The leaf insect has a green leaf-shaped body. It is adapted to be camouflaged among green leaves. The word camouflage means to blend in.
Now look at each animal. Figure out which animal has a similar adaptation.
The emerald tree boa has bright green scales covering its body. It is adapted to be camouflaged among green leaves.
The fox snake has a tan body with large brown spots. It is not adapted to be camouflaged among green leaves.


Question: Select the organism in the same species as the cocoi heron.

Choices:
- Taricha torosa
- Ardea goliath
- Ardea cocoi

This organism is a cocoi heron. Its scientific name is Ardea cocoi.

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 cocoi heron's scientific name is Ardea cocoi.
Ardea cocoi has the same scientific name as a cocoi heron. So, these organisms are in the same species.
Taricha torosa does not have the same scientific name as a cocoi heron. So, Ardea cocoi and Taricha torosa are not in the same species.
Ardea cocoi is in the same genus as Ardea goliath, but they are not in the same species.
Organisms in the same species have the same scientific names. Ardea cocoi and Ardea goliath are different species within the same genus.


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

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

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.

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

Choices:
- the surroundings . . . each pizza
- each pizza . . . the surroundings

Erica was delivering two identical pizzas to a customer. While driving to the customer's house, Erica put one of the pizza boxes on top of the other one. This table shows how the temperature of each pizza changed over 15minutes.

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


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

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

The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.

natural science

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

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


Question: Which country is highlighted?

Choices:
- Dominica
- Saint Vincent and the Grenadines
- Trinidad and Tobago
- Grenada

social science

Identify and select countries of the Caribbean

Solution: This country is Grenada.


Question: What is the capital of Minnesota?

Choices:
- Saint Paul
- Minneapolis
- Jefferson City
- Pierre

social science

Solution: Saint Paul is the capital of Minnesota.


Question: Which animal's feet are also adapted for digging?

Choices:
- groundhog
- tokay gecko

Star-nosed moles are found in many parts of North America. They live in burrows. The moles eat earthworms and nuts, which they find in the soil. The feet of the  are adapted for digging.
Figure: star-nosed mole.

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 star-nosed mole.
The star-nosed mole has long, straight claws. Its feet are adapted for digging. The star-nosed mole uses its claws to break up soil and move it out of the way.
Now look at each animal. Figure out which animal has a similar adaptation.
The groundhog has long, straight claws. Its feet are adapted for digging.
The tokay gecko has wide, sticky toes. Its feet are not adapted for digging. The tokay gecko uses its feet to climb trees and walk on leaves.


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

Choices:
- Do the insides of white boxes get hotter than the insides of black boxes when the boxes are left in the sun?
- Do the temperatures inside boxes depend on the sizes of the boxes?

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

Rhianna glued lids onto 16 cardboard shoe boxes of equal size. She painted eight of the boxes black and eight of the boxes white. Rhianna made a small hole in the side of each box and then stuck a thermometer partially into each hole so she could measure the temperatures inside the boxes. She placed the boxes in direct sunlight in her backyard. Two hours later, she measured the temperature inside each box. Rhianna compared the average temperature inside the black boxes to the average temperature inside the white boxes.
Figure: a shoebox painted black.

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 of the following was a dependent variable in this experiment?

Choices:
- the watering method used
- the change in weight for each plant

The passage below describes an experiment. Read the passage and think about the variables that are described.

Audrey had four air plants on her desk that were not growing. She suspected that they needed more water. Audrey's sister recommended soaking the air plants in a bowl of water once a week. Audrey's coworker recommended spraying the air plants with a mist of water every day.
Audrey decided to test both ideas. First, she measured the initial weight of all four air plants. Then, for the next two months, she sprayed two of the plants with a mist of water each day. She watered the two remaining plants by soaking them in water once a week. Finally, Audrey measured the weight of the plants again and calculated the change in weight for each plant.
Hint: An independent variable is a variable whose effect you are investigating. A dependent variable is a variable that you measure.
Figure: an air plant displayed on a rock.

natural science

Identify independent and dependent variables

Experiments have variables, or parts that change. You can design an experiment to find out how one variable affects another variable. For example, imagine that you want to find out if fertilizer affects the number of tomatoes a tomato plant grows. To answer this question, you decide to set up two equal groups of tomato plants. Then, you add fertilizer to the soil of the plants in one group but not in the other group. Later, you measure the effect of the fertilizer by counting the number of tomatoes on each plant.
In this experiment, the amount of fertilizer added to the soil and the number of tomatoes were both variables.
The amount of fertilizer added to the soil was an independent variable because it was the variable whose effect you were investigating. This type of variable is called independent because its value does not depend on what happens after the experiment begins. Instead, you decided to give fertilizer to some plants and not to others.
The number of tomatoes was a dependent variable because it was the variable you were measuring. This type of variable is called dependent because its value can depend on what happens in the experiment.


Question:
Complete the statement.
Hydrazine is ().

Choices:
- an elementary substance
- a compound

The model below represents a molecule of hydrazine. Hydrazine is used in some types of rocket fuels.

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 boron is B, and the atomic symbol for the chemical element chlorine is Cl.
Scientists use different types of models to represent substances whose atoms are bonded in different ways. One type of model is a ball-and-stick model. The ball-and-stick model below represents a molecule of the compound boron trichloride.
In a ball-and-stick model, the balls represent atoms, and the sticks represent bonds. Notice that the balls in the model above are not all the same color. Each color represents a different chemical element. The legend shows the color and the atomic symbol for each chemical element in the substance.

Solution:
Use the model to determine whether hydrazine is an elementary substance or a compound.
Step 1: Interpret the model.
.
Use the legend to determine the chemical element represented by each color. The colors and atomic symbols from the legend are shown in the table below. The table also includes the names of the chemical elements represented in the model.
You can see from the model that a molecule of hydrazine is composed of four hydrogen atoms and two nitrogen atoms bonded together.
Step 2: Determine whether the substance is an elementary substance or a compound.
You know from Step 1 that hydrazine is composed of two chemical elements: hydrogen and nitrogen. Since hydrazine is composed of multiple chemical elements bonded together, hydrazine is a compound.


Question: What is the probability that a chicken produced by this cross will be heterozygous for the leg color gene?

Choices:
- 2/4
- 0/4
- 4/4
- 3/4
- 1/4

In a group of chickens, some individuals have white legs and others have yellow legs. In this group, the gene for the leg color trait has two alleles. The allele for yellow legs (l) is recessive to the allele for white legs (L).
This Punnett square shows a cross between two chickens.

natural science

Use Punnett squares to calculate probabilities of offspring types

Offspring genotypes: homozygous or heterozygous?
How do you determine whether an organism is homozygous or heterozygous for a gene? Look at the alleles in the organism's genotype for that gene.
An organism with two identical alleles for a gene is homozygous for that gene.
If both alleles are dominant, the organism is homozygous dominant for the gene.
If both alleles are recessive, the organism is homozygous recessive for the gene.
An organism with two different alleles for a gene is heterozygous for that gene.
In a Punnett square, each box represents a different outcome, or result. Each of the four outcomes is equally likely to happen. Each box represents one way the parents' alleles can combine to form an offspring's genotype.
Because there are four boxes in the Punnett square, there are four possible outcomes.
An event is a set of one or more outcomes. The probability of an event is a measure of how likely the event is to happen. This probability is a number between 0 and 1, and it can be written as a fraction:
probability of an event = number of ways the event can happen / number of equally likely outcomes
You can use a Punnett square to calculate the probability that a cross will produce certain offspring. For example, the Punnett square below has two boxes with the genotype Ff. It has one box with the genotype FF and one box with the genotype ff. This means there are two ways the parents' alleles can combine to form Ff. There is one way they can combine to form FF and one way they can combine to form ff.
 | F | f
F | FF | Ff
f | Ff | ff
Consider an event in which this cross produces an offspring with the genotype ff. The probability of this event is given by the following fraction:
number of ways the event can happen / number of equally likely outcomes = number of boxes with the genotype ff / total number of boxes = 1 / 4


Question: Which of these continents does the prime meridian intersect?

Choices:
- Africa
- Australia
- Asia

social science

Lines of latitude and lines of longitude are imaginary lines drawn on some globes and maps. They can help you find places on globes and maps.
Lines of latitude show how far north or south a place is. We use units called degrees to describe how far a place is from the equator. The equator is the line located at 0° latitude. We start counting degrees from there.
Lines north of the equator are labeled N for north. Lines south of the equator are labeled S for south. Lines of latitude are also called parallels because each line is parallel to the equator.
Lines of longitude are also called meridians. They show how far east or west a place is. We use degrees to help describe how far a place is from the prime meridian. The prime meridian is the line located at 0° longitude. Lines west of the prime meridian are labeled W. Lines east of the prime meridian are labeled E. Meridians meet at the north and south poles.
The equator goes all the way around the earth, but the prime meridian is different. It only goes from the North Pole to the South Pole on one side of the earth. On the opposite side of the globe is another special meridian. It is labeled both 180°E and 180°W.
Together, lines of latitude and lines of longitude form a grid. You can use this grid to find the exact location of a place.

Solution: The prime meridian is the line at 0° longitude. It intersects Africa. It does not intersect Australia or Asia.


Question: Is a ruler 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 shape of its own.
Some solids can be bent or broken easily. Others are hard to bend or break.
A glass cup is a solid. A sock is also a solid.
When matter is a liquid, it takes the shape of its container.
Think about pouring a liquid from a cup into a bottle. The shape of the liquid is different in the cup than in the bottle. But the liquid still takes up the same amount of space.
Juice is a liquid. Honey is also a liquid.
When matter is a gas, it spreads out to fill a space.
Many gases are invisible. So, you can’t see them. Air is a gas.

Solution:
A ruler is a solid. A solid has a size and shape of its own.
If you put a ruler in a box, the ruler will keep its shape.


Question: Which country is highlighted?

Choices:
- the Marshall Islands
- New Zealand
- Vanuatu
- Nauru

social science

Identify and select countries of Oceania

Solution: This country is Nauru.


Question:
Complete the sentence.
The Western Alps formed at a () boundary.

Choices:
- transform
- convergent
- divergent

Read the passage and look at the picture.
Millions of years ago, the Eurasian Plate and the African Plate began to move toward each other, eventually colliding. This plate motion formed many mountain ranges, including the Western Alps. The Western Alps run through European countries, including France, Italy, and Switzerland.

natural science

Describe tectonic plate boundaries around the world

The outer layer of Earth is broken up into many pieces called tectonic plates, or simply plates. The breaks between plates are called plate boundaries. Plate boundaries are classified by the way the plates are moving relative to each other:
At a divergent boundary, two plates are moving away from each other.
At a transform boundary, two plates are sliding past each other.
At a convergent boundary, two plates are moving toward each other.
One type of convergent boundary is a continent-continent collision. This type of boundary forms when two plates with continental crust move toward each other. The collision compresses and folds the continental crust, forcing it upward to form a mountain range.

Solution:
To figure out what type of plate boundary formed the Western Alps, you need to know how the tectonic plates interacted. To find this out, read the passage carefully.
Millions of years ago, the Eurasian Plate and the African Plate began to move toward each other, eventually colliding. This plate motion formed many mountain ranges, including the Western Alps. The Western Alps run through European countries, including France, Italy, and Switzerland.
The underlined part of the passage explains that the Western Alps formed as the two plates collided, or ran into each other. For two plates to collide, they must be moving toward each other. So, the Western Alps formed at a convergent boundary.


Question: What is the capital of Vermont?

Choices:
- Omaha
- Montpelier
- Boston
- Burlington

social science

Identify state capitals of the Northeast

Solution: Montpelier is the capital of Vermont.


Question: Which animal's feet are also adapted for grabbing prey?

Choices:
- brahminy kite
- dromedary camel

White-tailed eagles eat fish, mammals, and other birds. The 's feet are adapted for grabbing prey.
Figure: white-tailed eagle.

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 white-tailed eagle.
The white-tailed eagle has long toes with sharp claws. Its feet are adapted for grabbing prey. The sharp claws can help the white-tailed eagle attack and kill its prey. The long toes can help it hold on to its prey.
Now look at each animal. Figure out which animal has a similar adaptation.
The brahminy kite has long toes with sharp claws. Its feet are adapted for grabbing prey.
The dromedary camel has large pads on the bottoms of its feet. Its feet are not adapted for grabbing prey. The dromedary camel uses its feet to walk on sand.


Question: What is the name of the colony shown?

Choices:
- South Carolina
- Connecticut
- Massachusetts
- Georgia

social science

Solution: The colony is Connecticut.


Question: Which of these states is farthest west?

Choices:
- Georgia
- Iowa
- New York
- North Dakota

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 west arrow is pointing. North Dakota is farthest west.


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, but some of them are different 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 changing the distance between them. The magnitude of the magnetic force is greater when there is a smaller distance between the magnets.

Solution:
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: Which ocean is highlighted?

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


Question: What can Ernesto and Lucia trade to each get what they want?

Choices:
- Ernesto can trade his tomatoes for Lucia's sandwich.
- Ernesto can trade his tomatoes for Lucia's broccoli.
- Lucia can trade her almonds for Ernesto's tomatoes.
- Lucia can trade her broccoli for Ernesto'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.
Ernesto and Lucia open their lunch boxes in the school cafeteria. Both of them could be happier with their lunches. Ernesto wanted broccoli in his lunch and Lucia was hoping for tomatoes. Look at the images of their lunches. Then answer the question below.

social science

Solution:
Ernesto wanted broccoli in his lunch and Lucia was hoping for tomatoes. Look at the labeled part of the images.
Ernesto has tomatoes. Lucia 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 Nevada?

Choices:
- Baltimore
- Helena
- Carson City
- Baton Rouge

social science

Solution: Carson City is the capital of Nevada.


Question: Which plant can produce spores?

Choices:
- a mature fern
- a heart-shaped plant

This diagram shows the life cycle of a fern.

natural science

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

Solution:
A mature fern can make spores. Spores grow inside the spore case. When the spore case breaks open, the spores are released.
A heart-shaped plant produces eggs and sperm, not spores.


Question: Which of the following organisms is the primary consumer in this food web?

Choices:
- sea otter
- kelp
- plainfin midshipman
- phytoplankton

Below is a food web from an ocean ecosystem in Monterey Bay, off the coast of California.
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:
Primary consumers eat producers. So, in a food web, primary consumers have arrows pointing to them from producers.
The phytoplankton does not have any arrows pointing to it. So, the phytoplankton is not a primary consumer.
The plainfin midshipman has an arrow pointing to it from the phytoplankton. The phytoplankton is a producer, so the plainfin midshipman is a primary consumer.
The sea otter has an arrow pointing to it from the sea urchin. The sea urchin is not a producer. So, the sea otter is not a primary consumer.
The kelp does not have any arrows pointing to it. So, the kelp is not a primary consumer.
The kelp bass has an arrow pointing to it from the kelp. The kelp is a producer, so the kelp bass is a primary consumer.


Question: What is the capital of Colorado?

Choices:
- Denver
- Dallas
- Sioux Falls
- Green Bay

social science

Solution: Denver is the capital of Colorado.


Question: Will these magnets attract or repel each other?

Choices:
- repel
- attract

Two magnets are placed as shown.

Hint: Magnets that attract pull together. Magnets that repel push apart.

natural science

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

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


Question: Which country is highlighted?

Choices:
- Dominica
- the Dominican Republic
- Jamaica
- Haiti

social science

Identify and select countries of the Caribbean

Solution:
This country is the Dominican Republic.
Why does the Dominican Republic share its island with another country?
The Dominican Republic and Haiti share the island of Hispaniola. It is home to the earliest European settlements in the Americas. Christopher Columbus founded the first European settlement on the island in 1492 during his first voyage across the Atlantic.
Though many people lived on the island before Columbus's arrival, European countries quickly began to colonize the island. Eventually France and Spain both established colonies. The Spanish colony eventually became the country of the Dominican Republic, and the French colony eventually became the country of Haiti. Today, people in the two countries speak different languages and have many cultural differences.


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

Choices:
- a gas
- a solid
- 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 handsaw is a solid. A solid has a size and shape of its own.
The handle of this handsaw is made of wood, and the blade is made of metal. Both wood and metal are solids.


Question: Which continent is highlighted?

Choices:
- Europe
- North America
- South America
- Asia

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 North America.


Question: What can Nolan and Dalton trade to each get what they want?

Choices:
- Nolan can trade his tomatoes for Dalton's broccoli.
- Nolan can trade his tomatoes for Dalton's carrots.
- Dalton can trade his broccoli for Nolan's oranges.
- Dalton can trade his almonds for Nolan'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.
Nolan and Dalton open their lunch boxes in the school cafeteria. Neither Nolan nor Dalton 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.
Nolan's lunch Dalton's lunch

social science

Solution:
Look at the table and images.
Nolan wants broccoli. Dalton 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 Idaho?

Choices:
- Georgetown
- Boise
- Nampa
- Olympia

social science

Solution: Boise is the capital of Idaho.


Question: Which country is highlighted?

Choices:
- Cuba
- the Dominican Republic
- Saint Lucia
- Saint Vincent and the Grenadines

social science

Identify and select countries of the Caribbean

Solution: This country is Saint Lucia.