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

Choices:
- bat star
- phytoplankton
- kelp bass

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: Use the arrows to follow how matter moves through this food web. For each answer choice, try to find a path of arrows to the sea cucumber.There is one path matter can take from the kelp to the sea cucumber: kelp->sea urchin->sea otter->orca->sea cucumber. kelp bass. The only arrow pointing from the kelp bass leads to the bat star. No arrows point from the bat star to any other organisms. So, in this food web, matter does not move from the kelp bass to the sea cucumber.. bat star. No arrows point from the bat star to any other organisms. So, in this food web, matter does not move from the bat star to the sea cucumber.. There are two paths matter can take from the phytoplankton to the sea cucumber: phytoplankton->plainfin midshipman->sea cucumber. phytoplankton->zooplankton->plainfin midshipman->sea cucumber.


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

Choices:
- a tail fin
- a large red lump on its head
- long legs

This picture shows a fossil of an animal called Holophagus. Holophagus lived in the ocean and gave birth to live young.

natural science

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


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

Choices:
- scratchy
- bendable

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 scratchy object is rough and itchy against your skin. The bubble gum is not scratchy.
A bendable object can be bent without breaking. Both objects are bendable.
The property that both objects have in common is bendable.


Question: Identify the question that Albert and Tucker's experiment can best answer.

Choices:
- Do ping pong balls travel farther when launched from a 30° angle compared to a 45° angle?
- Do ping pong balls stop rolling along the ground sooner after being launched from a 30° angle or a 45° angle?

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

Albert placed a ping pong ball in a catapult, pulled the catapult's arm back to a 45° angle, and launched the ball. Then, Albert launched another ping pong ball, this time pulling the catapult's arm back to a 30° angle. With each launch, his friend Tucker measured the distance between the catapult and the place where the ball hit the ground. Albert and Tucker repeated the launches with ping pong balls in four more identical catapults. They compared the distances the balls traveled when launched from a 45° angle to the distances the balls traveled when launched from a 30° angle.
Figure: a catapult for launching ping pong balls.

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 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: Which animal's feet are also adapted for swimming?

Choices:
- tokay gecko
- European river otter

White-breasted cormorants live near lakes, marshes, and the sea in southern Africa. They eat mostly fish, which they catch while swimming and diving. The feet of the  are adapted for swimming.
Figure: white-breasted cormorant.

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-breasted cormorant.
The white-breasted cormorant has webbed feet. Its feet are adapted for swimming. As it swims, the white-breasted cormorant uses its webbed feet to push itself through water.
Now look at each animal. Figure out which animal has a similar adaptation.
The European river otter has webbed feet. Its feet are adapted for swimming.
The tokay gecko has wide, sticky toes. Its feet are not adapted for swimming. The tokay gecko uses its feet to climb trees and walk on leaves.


Question: Which property matches this object?

Choices:
- bouncy
- bendable

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 bouncy object will bounce back from the floor if you drop it. The belt is not bouncy.
A bendable object can be bent without breaking. The belt is bendable.


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

Choices:
- The magnitude of the magnetic force is smaller in Pair 2.
- The magnitude of the magnetic force is smaller 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 smaller when there is a greater distance between the magnets.

Solution:
The magnets in Pair 1 attract. The magnets in Pair 2 repel. But whether the magnets attract or repel affects only the direction of the magnetic force. It does not affect the magnitude of the magnetic force.
Distance affects the magnitude of the magnetic force. When there is a 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: What is the capital of Pennsylvania?

Choices:
- Juneau
- Providence
- Harrisburg
- Pittsburgh

social science

Identify state capitals of the Northeast

Solution: Harrisburg is the capital of Pennsylvania.


Question: In this food chain, the persimmon is a producer. Why?

Choices:
- It eats another organism.
- It makes its own food.

This diagram shows a food chain from a forest ecosystem in Virginia.

natural science

Every organism needs food to stay alive. Organisms get their food in different ways. A food chain shows how organisms in an ecosystem get their food.
Producers make their own food. Many producers use carbon dioxide, water, and sunlight to make sugar. This sugar is food for the producer.
Consumers eat other organisms. Consumers cannot make their own food.

Solution: In this food chain, the persimmon is a producer because it makes its own food. The persimmon uses carbon dioxide, water, and sunlight to make its own food.


Question: What is the capital of Virginia?

Choices:
- Richmond
- Arlington
- Norfolk
- Atlanta

social science

Identify state capitals of the Southeast

Solution: Richmond is the capital of Virginia.


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

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

The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.

natural science

Identify how particle motion affects temperature and pressure

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

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


Question: What is the capital of Arizona?

Choices:
- Phoenix
- Juneau
- Helena
- Salt Lake City

social science

Solution: Phoenix is the capital of Arizona.


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

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

The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.

natural science

Identify how particle motion affects temperature and pressure

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

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


Question: Look at the models of molecules below. Select the elementary substance.

Choices:
- oxygen
- bromomethane
- methane

natural science

Identify 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.


Question: Select the bird below.

Choices:
- fruit bat
- sea eagle

Birds have feathers, two wings, and a beak. A white stork is an example of a bird.

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 sea eagle is a bird. It has feathers, two wings, and a beak.
Sea eagles use their sharp beaks to eat fish and other birds.
A fruit bat is a mammal. It has hair and feeds its young milk.
Fruit bats eat fruit and drink nectar from flowers. They have special teeth to help them bite through fruit skins.


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

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

The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.

natural science

Identify how particle motion affects temperature and pressure

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

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


Question: Select the mammal below.

Choices:
- loon
- great white shark
- albatross
- Tasmanian devil

Mammals have hair or fur and feed their young milk.
Mammals are warm-blooded. Warm-blooded animals can control their body temperature.
A koala is an example of a mammal.

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 loon is a bird. It has feathers, two wings, and a beak.
Loons usually live near lakes. They dive in the water to hunt for food.
An albatross is a bird. It has feathers, two wings, and a beak.
Albatrosses live near the ocean. They hunt squid, fish, and other small animals.
A Tasmanian devil is a mammal. It has fur and feeds its young milk.
Tasmanian devils are meat-eating marsupials. They live on the island of Tasmania, near Australia.
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.


Question: What can Clare and Adele trade to each get what they want?

Choices:
- Clare can trade her tomatoes for Adele's broccoli.
- Adele can trade her broccoli for Clare's oranges.
- Adele can trade her almonds for Clare's tomatoes.
- Clare can trade her tomatoes for Adele's carrots.

Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another.
Clare and Adele open their lunch boxes in the school cafeteria. Neither Clare nor Adele 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.
Clare's lunch Adele's lunch

social science

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


Question: Which continent is highlighted?

Choices:
- Europe
- Africa
- Asia

social science

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

Solution: This continent is Asia.


Question: What is the name of the colony shown?

Choices:
- Vermont
- New Hampshire
- Massachusetts
- Connecticut

social science

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


Question: What is the capital of Wisconsin?

Choices:
- Milwaukee
- Juneau
- Honolulu
- Madison

social science

Solution: Madison is the capital of Wisconsin.


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

Choices:
- water rail
- European beaver

Parakeet auklets are small seabirds that live in the Pacific Ocean. They eat mostly crustaceans, which they catch while swimming and diving. The feet of the  are adapted for swimming.
Figure: parakeet auklet.

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 parakeet auklet.
The parakeet auklet has webbed feet. Its feet are adapted for swimming. As it swims, the parakeet auklet uses its webbed feet to push itself through water.
Now look at each animal. Figure out which animal has a similar adaptation.
The European beaver has webbed feet. Its feet are adapted for swimming.
The water rail has very long toes. Its feet are not adapted for swimming. The water rail uses its feet to walk on muddy ground.


Question: What is the capital of Colorado?

Choices:
- Salt Lake City
- Colorado Springs
- Denver
- Boulder

social science

Solution: Denver is the capital of Colorado.


Question: Which continent is highlighted?

Choices:
- Asia
- Africa
- South America
- Australia

social science

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

Solution: This continent is South America.


Question: Which continent is highlighted?

Choices:
- South America
- North America
- Asia
- Africa

social science

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

Solution: This continent is Africa.


Question: What is the capital of Maryland?

Choices:
- Concord
- Honolulu
- Baltimore
- Annapolis

social science

Identify state capitals of the Northeast

Solution: Annapolis is the capital of Maryland.


Question: Which animal is also adapted for climbing trees?

Choices:
- lama
- red-shanked douc

Vervet monkeys live in the grasslands and forests of Africa. They climb trees to find food and shelter. The 's hands and feet are adapted for climbing trees.
Figure: vervet monkey.

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 vervet monkey.
The vervet monkey has long fingers and toes. It is adapted for climbing trees. The vervet monkey uses its long fingers and toes to hold on to branches while climbing.
Now look at each animal. Figure out which animal has a similar adaptation.
The red-shanked douc has long fingers and toes. It is adapted for climbing trees.
The lama has four hoofed feet. It is not adapted for climbing trees. The lama uses its feet to walk and run.


Question: What is the probability that a scarlet rosemallow plant produced by this cross will have white flowers?

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

In a group of scarlet rosemallow plants, some individuals have red flowers and others have white flowers. In this group, the gene for the flower color trait has two alleles. The allele for white flowers (f) is recessive to the allele for red flowers (F).
This Punnett square shows a cross between two scarlet rosemallow plants.

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 solution has a higher concentration of purple particles?

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

The diagram below is a model of two solutions. Each purple 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 purple particles represent the solute. To figure out which solution has a higher concentration of purple particles, look at both the number of purple particles and the volume of the solvent in each container.
Use the concentration formula to find the number of purple particles per milliliter.
Solution A has more purple particles per milliliter. So, Solution A has a higher concentration of purple particles.


Question: What is the capital of New Mexico?

Choices:
- Albuquerque
- Santa Fe
- Helena
- Juneau

social science

Solution: Santa Fe is the capital of New Mexico.


Question: Which continent is highlighted?

Choices:
- Antarctica
- Asia
- Africa
- Europe

social science

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

Solution: This continent is Africa.


Question: Which country is highlighted?

Choices:
- Haiti
- Jamaica
- Cuba
- The Bahamas

social science

Identify and select countries of the Caribbean

Solution:
This country is Haiti.
Does Haiti have any territorial disputes?
Haiti claims to own Navassa Island, which is a disputed territory. In other words, multiple countries or groups claim that the area rightfully belongs to them.
Navassa Island is also claimed by the United States. The United States claimed the island in 1857 and has controlled it since then. But Haiti considers the island part of its territory and has protested the United States' claim since this time. No one lives on the island. Today, it is a nature preserve.


Question: What is the name of the colony shown?

Choices:
- Pennsylvania
- Wisconsin
- New York
- Florida

social science

Solution: The colony is Pennsylvania.


Question: Which better describes the tide pool ecosystems in Salt Point State Park?

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

Figure: Salt Point State Park.
Salt Point State Park is in northern California. The park is on the coast of the Pacific Ocean. It has many tide pool ecosystems.

natural science

An ecosystem is formed when living and nonliving things interact in an environment. There are many types of ecosystems. Here are some ways in which ecosystems can differ from each other:
the pattern of weather, or climate
the type of soil or water
the organisms that live there

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


Question: What is the capital of Idaho?

Choices:
- Portland
- Nampa
- Columbus
- Boise

social science

Solution: Boise is the capital of Idaho.


Question: Which animal's body is better adapted for protection against a predator with sharp teeth?

Choices:
- eastern rat snake
- nautilus

Painted turtles are adapted to protect themselves from a predator with sharp teeth. They have hard outer shells covering their bodies. A  can pull its head and legs into its shell when attacked.
Figure: painted turtle.

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 painted turtle.
The painted turtle has a hard outer shell. Its body is adapted for protection against a predator with sharp teeth. The hard shell makes it difficult for predators to hurt or kill the painted turtle.
Now look at each animal. Figure out which animal has a similar adaptation.
The nautilus has a hard outer shell. Its body is adapted for protection against a predator with sharp teeth.
The eastern rat snake has soft scales covering its skin. Its body is not adapted for protection against predators with sharp teeth.


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

Choices:
- climate
- weather

Figure: Eastern Colorado.
Eastern Colorado is part of the Great Plains. On October 19, 1988, a thunderstorm near the town of La Junta produced winds of 63 miles per hour.
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.
Eastern Colorado is part of the Great Plains. On October 19, 1988, a thunderstorm near the town of La Junta produced winds of 63 miles per hour.
The underlined part of the passage tells you about the wind speed in Eastern Colorado on October 19, 1988. This passage describes the atmosphere at a certain place and time. So, this passage describes the weather.


Question: Which country is highlighted?

Choices:
- Tonga
- Fiji
- Nauru
- Samoa

social science

Identify and select countries of Oceania

Solution: This country is Samoa.


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

Choices:
- climate
- weather

Figure: Dhaka.
Dhaka is the capital of Bangladesh, a country in southern Asia. The city is humid most days of the year.
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.

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.
Dhaka is the capital of Bangladesh, a country in southern Asia. The city is humid most days of the year.
The underlined part of the passage tells you about the usual pattern of humidity in Dhaka. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.


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

Choices:
- if the spacecraft was damaged when using a parachute with a 1 m vent going 200 km per hour
- how steady a parachute with a 1 m vent was at 200 km per hour
- whether a parachute with a 1 m vent would swing too much at 400 km per hour

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.

Kenji was an aerospace engineer who was developing a parachute for a spacecraft that would land on Mars. He needed to add a vent at the center of the parachute so the spacecraft would land smoothly. However, the spacecraft would have to travel at a high speed before landing. If the vent was too big or too small, the parachute might swing wildly at this speed. The movement could damage the spacecraft.
So, to help decide how big the vent should be, Kenji put a parachute with a 1 m vent in a wind tunnel. The wind tunnel made it seem like the parachute was moving at 200 km per hour. He observed the parachute to see how much it swung.
Figure: a spacecraft's parachute in a wind tunnel.

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 better describes the Scarborough Marsh ecosystem?

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

Figure: Scarborough Marsh.
Scarborough Marsh is a wetland ecosystem in southern Maine.

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, Scarborough Marsh has land that is covered with water during most of the year. It also has other water ecosystems nearby.


Question: Which animal's legs are also adapted for wading?

Choices:
- African fish eagle
- great egret

Flamingos live near marshes, rivers, and oceans. They eat small crustaceans that live in shallow water. Flamingos get their food by walking through water, or wading.
The 's legs are adapted for wading. They are lightweight and keep the bird's body above the water.
Figure: flamingo.

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 flamingo.
Long legs help the flamingo keep its body above the surface of the water while wading. Thin legs are easier to move through the water.
Now look at each animal. Figure out which animal has a similar adaptation.
The great egret has long, thin legs. Its legs are adapted for wading.
The African fish eagle has short legs. Its legs are not adapted for wading. The African fish eagle uses its legs to walk and perch.


Question: Is the air from a hair dryer 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:
The air from a hair dryer is a gas. A gas expands to fill a space.
A hair dryer uses a fan to blow warm air out. When the air leaves the hair dryer, the air expands to fill a much large space.


Question: Why do adult cats meow?

Choices:
- to act like kittens
- to talk to other cats
- to talk to people

Read the text about cat meows.
While kittens meow to their mothers, they stop once they are old enough to take care of themselves. At that point, cats use smell, touch, and body language to talk to each other. So if adult cats aren't making noise for each other, why do cats meow? Cats meow to talk with their humans!
If you are a cat owner, you may be interested in understanding your cat's meows. Different meows can have distinct meanings. A short, high squeak or chirp is a cheerful hello. A louder and longer meow is a cat's way of saying "Please?" or "Let me out!" An even longer and louder meow is your cat's way of demanding something, like "Food! Now!" Of course, the best cat sound to many cat owners is a low, rumbling purr that comes from a happy cat.

language science

Solution:
Look at the text in bold below. It tells you why adult cats meow.
While kittens meow to their mothers, they stop once they are old enough to take care of themselves. At that point, cats use smell, touch, and body language to talk to each other. So if adult cats aren't making noise for each other, why do cats meow? Cats meow to talk with their humans!


Question: Is Daphnia pulex made up of one cell?

Choices:
- no
- yes

This organism is Daphnia pulex. It is a member of the animal kingdom.
Daphnia pulex lives in lakes and ponds. D. pulex can sense chemicals that its predators release into the water. When D. pulex senses that a predator is nearby, it can grow sharp spikes on its head! These spikes make D. pulex harder to eat.

natural science

Describe, classify, and compare kingdoms

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

Solution: Daphnia pulex is an animal. Animals are made up of many cells.


Question: Which property matches this object?

Choices:
- blue
- stretchy

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it.

Solution:
Look at the object.
Think about each property.
A stretchy object gets longer when you pull on it. The bubble gum is stretchy.
Blue is a color.
This color is blue. The bubble gum is not blue.


Question: Which material is this jacket made of?

Choices:
- metal
- clay

natural science

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

Solution:
Look at the picture of the jacket.
The jacket is made of two different materials. The buckles are made of metal. The rest of the jacket is made of leather.
Not all shiny jackets are made of leather. Some are made from other fabrics designed to look like leather.


Question: Which of these states is farthest north?

Choices:
- New Mexico
- Missouri
- Virginia
- Pennsylvania

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 north arrow is pointing. Pennsylvania is farthest north.


Question: Which country is highlighted?

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

social science

Identify and select countries of Oceania

Solution: This country is Solomon Islands.


Question: Which country is highlighted?

Choices:
- Fiji
- Solomon Islands
- Australia
- the Marshall Islands

social science

Identify and select countries of Oceania

Solution: This country is Solomon Islands.


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


Question: Which i in column 4?

Choices:
- the police department
- the theater
- the grocery store
- the fire department

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 grocery store is in column 4.


Question: What is the capital of Idaho?

Choices:
- Denver
- Indianapolis
- Nampa
- Boise

social science

Solution: Boise is the capital of Idaho.


Question: Which country is highlighted?

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

social science

Identify and select countries of Oceania

Solution: This country is the Federated States of Micronesia.


Question: What is the capital of Hawaii?

Choices:
- Boise
- Hilo
- Honolulu
- Santa Fe

social science

Solution: Honolulu is the capital of Hawaii.


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

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

The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.

natural science

Identify how particle motion affects temperature and pressure

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

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


Question: Is a T-shirt a solid, a liquid, or a gas?

Choices:
- a liquid
- a gas
- a solid

natural science

Identify and sort solids, liquids, and gases

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

Solution: A T-shirt is a solid. You can fold a T-shirt. But it will still have a size and shape of its own.


Question: Which country is highlighted?

Choices:
- Australia
- Fiji
- Tuvalu
- Solomon Islands

social science

Identify and select countries of Oceania

Solution: This country is Fiji.


Question: What is the capital of Arizona?

Choices:
- Juneau
- Phoenix
- Provo
- Newport

social science

Solution: Phoenix is the capital of Arizona.


Question: What is the capital of Kansas?

Choices:
- Bismarck
- Indianapolis
- Topeka
- Burlington

social science

Solution: Topeka is the capital of Kansas.


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

Choices:
- the surroundings . . . each bottle
- each bottle . . . the surroundings

Two bottles of soda were sitting on a porch on a hot day. The two bottles were identical, except that one bottle was made of brown glass and one bottle was made of clear glass. This table shows how the temperature of each bottle changed over 25minutes.

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


Question: What can Shivani and Austin trade to each get what they want?

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

Trade happens when people agree to exchange goods and services. People give up something to get something else. Sometimes people barter, or directly exchange one good or service for another.
Shivani and Austin open their lunch boxes in the school cafeteria. Neither Shivani nor Austin 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.
Shivani's lunch Austin's lunch

social science

Solution:
Look at the table and images.
Shivani wants broccoli. Austin 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: Compare the average kinetic energies of the particles in each sample. Which sample has the higher temperature?

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

The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.

natural science

Identify how particle motion affects temperature and pressure

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

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


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

Choices:
- hanging parrot
- sand martin

s eat insects and other small invertebrates. The shape of the 's beak is adapted to catch insects.
Figure: European nightjar.

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 European nightjar.
A short, thin beak is light and easy to move. The European nightjar uses its beak to grab fast-moving insects while flying.
Now look at each bird. Figure out which bird has a similar adaptation.
The sand martin has a short, thin beak. Its beak is adapted to catch insects.
The hanging parrot has a small hooked beak. Its beak is not adapted to catch insects. The hanging parrot uses its beak to eat fruit and seeds.


Question: Which continent is highlighted?

Choices:
- Europe
- Africa
- Asia
- Antarctica

social science

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

Solution: This continent is Asia.


Question:
Complete the statement.
Iodine is ().

Choices:
- an elementary substance
- a compound

The model below represents a molecule of iodine. odine is found in some types of disinfectants.

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 iodine is an elementary substance or a compound.
Step 1: Interpret the model.
In the ball-and-stick model shown above, both of the balls are the same color:
. The legend shows that dark purple represents the chemical element with the atomic symbol I. So, the model shows you that a molecule of iodine is composed of one chemical element.
Step 2: Determine whether the substance is an elementary substance or a compound.
You know from Step 1 that iodine is composed of only one chemical element. So, iodine is an elementary substance.


Question: What is the capital of Indiana?

Choices:
- Des Moines
- Burlington
- Fort Wayne
- Indianapolis

social science

Solution: Indianapolis is the capital of Indiana.


Question: What is the capital of Virginia?

Choices:
- Jefferson City
- Richmond
- Jackson
- Norfolk

social science

Identify state capitals of the Southeast

Solution: Richmond is the capital of Virginia.


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

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

The diagram below is a model of two solutions. Each pink 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 pink particles represent the solute. To figure out which solution has a higher concentration of pink particles, look at both the number of pink particles and the volume of the solvent in each container.
Use the concentration formula to find the number of pink particles per milliliter.
Solution A and Solution B have the same number of pink particles per milliliter. So, their concentrations are the same.


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 1.
- The magnitude of the magnetic force is smaller 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 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.


Question: What is the name of the colony shown?

Choices:
- Delaware
- New Hampshire
- Michigan
- Pennsylvania

social science

Solution: The colony is Pennsylvania.


Question: Which property matches this object?

Choices:
- blue
- hard

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 hard object keeps its shape when you squeeze it. The slippers are not hard.
Blue is a color.
This color is blue. The slippers are blue.


Question: Based on the bubble map, which statement is true?

Choices:
- Kangaroos eat grass.
- Kangaroos sleep during the day.

language science

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

Solution:
A bubble map uses lines to connect things that are related. This bubble map shows information about different kinds of marsupials.
Kangaroos is directly connected to eat grass. This tells you that kangaroos eat grass.


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

Choices:
- bouncy
- blue
- transparent

natural science

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

Solution:
Look at each object.
For each object, decide if it has that property.
You can see clearly through a transparent object. None of the objects are transparent.
A bouncy object will bounce back from the floor if you drop it. The jeans and the yarn pom pom are not bouncy.
Blue is a color.
This color is blue. All three objects are blue.
The property that all three objects have in common is blue.


Question: What is the capital of South Carolina?

Choices:
- Charleston
- Lexington
- Columbia
- Topeka

social science

Identify state capitals of the Southeast

Solution: Columbia is the capital of South Carolina.


Question: Which state is highlighted?

Choices:
- Nebraska
- Iowa
- Kansas
- Missouri

social science

Solution: This state is Kansas.


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

Choices:
- Atlanta has a rainy season and a dry season.
- October has the highest average precipitation.
- Precipitation does not change much from month to month in Atlanta.

Use the graph to answer the question below.

natural science

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

Solution:
To describe the average precipitation trends in Atlanta, look at the graph.
Choice "Oct" is incorrect.
Choice "Precipitation does not change much from month to month in Atlanta." is incorrect.
The average monthly precipitation changes only slightly throughout the year.
Choice "Atlanta has a rainy season and a dry season." is incorrect.
The average monthly precipitation does not change much throughout the year. Every month has rain, and there is no dry season.
Choice "October has the highest average precipitation." is incorrect.
Most other months have a slightly higher average precipitation than October.


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

Choices:
- The magnitude of the magnetic force is smaller in Pair 1.
- The magnitude of the magnetic force is the same in both pairs.
- The magnitude of the magnetic force is smaller 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 strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other.

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


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

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

The diagram below is a model of two solutions. Each green 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 green particles represent the solute. To figure out which solution has a higher concentration of green particles, look at both the number of green particles and the volume of the solvent in each container.
Use the concentration formula to find the number of green particles per milliliter.
Solution A has more green particles per milliliter. So, Solution A has a higher concentration of green particles.


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

Choices:
- Do steel nails rust in fewer days when submerged in a large volume of liquid compared to a small volume?
- Do steel nails take fewer days to rust in water compared to vinegar?

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

Ben put one two-inch steel nail into each of six test tubes. He added water to three of the test tubes and vinegar to the other three. In each test tube, he completely covered the nail with the same volume of liquid. Ben checked the nails for rust at the same time every day. He recorded how many days it took each nail to become completely covered in rust. Then, he compared the number of days it took nails to rust in water to the number of days it took nails to rust in vinegar.
Figure: a new steel nail on a pile of rusty nails.

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: What is the capital of Illinois?

Choices:
- Louisville
- Springfield
- Phoenix
- Chicago

social science

Solution: Springfield is the capital of Illinois.


Question: Which number marks the New England Colonies?

Choices:
- 1
- 3
- 2

The map below shows the Thirteen Colonies in 1750.

social science

New England colonies: religion and government

Solution: The area that became Vermont was never a colony of its own.


Question: What is the capital of California?

Choices:
- Salem
- Sacramento
- Los Angeles
- Tallahassee

social science

Solution: Sacramento is the capital of California.


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

Choices:
- ginkgo leaf
- insect

This diagram shows fossils in an undisturbed sedimentary rock sequence.

natural science

Compare ages of fossils in a rock sequence

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

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


Question: Which country is highlighted?

Choices:
- Jamaica
- Grenada
- the Dominican Republic
- Saint Vincent and the Grenadines

social science

Identify and select countries of the Caribbean

Solution: This country is Saint Vincent and the Grenadines.


Question: Which of these states is farthest west?

Choices:
- North Carolina
- Ohio
- New Hampshire
- Arizona

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. Arizona is farthest west.


Question: Which of the following statements describess living in an independent city-state?

Choices:
- I live by myself in the wilderness.
- My city rules itself and is not part of a larger country.
- I vote for a president that rules over many different cities.
- All the decisions about my city are made by a faraway emperor.

Athens was one of the most powerful independent city-states in ancient Greece. Look at the definitions below. Then answer the question.

social science

Solution:
Look at the definitions.
Putting the definitions together, an independent city-state is a self-ruling city with its own government. So, a city-state rules itself and is not part of a larger country.
The ancient Greeks called a city-state a polis, which was the ancient Greek word for city. Today, the root word "polis" is in the name of many cities, such as Minneapolis in Minnesota or Annapolis in Maryland.


Question: Is an arrowhead a solid or a liquid?

Choices:
- a solid
- a liquid

natural science

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

Solution:
An arrowhead is a solid. A solid has a size and shape of its own.
An arrowhead is made of rock.


Question: What is the capital of North Carolina?

Choices:
- Tallahassee
- Plymouth
- Charlotte
- Raleigh

social science

Identify state capitals of the Southeast

Solution: Raleigh is the capital of North Carolina.


Question: What is the capital of Wyoming?

Choices:
- Orlando
- Laramie
- Salt Lake City
- Cheyenne

social science

Solution: Cheyenne is the capital of Wyoming.


Question: Which type of force from the boy moves the cart forward?

Choices:
- pull
- push

A boy shops for food. He applies a force to a shopping cart 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: The boy applies a force to the shopping cart to move it forward. The direction of this force is away from the boy. This force is a push.


Question: What can Krysta and Malik trade to each get what they want?

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

social science

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


Question: Which better describes the Gobi Desert ecosystem?

Choices:
- It has long, cold winters. It also has a small amount of rain or snow.
- It has warm, wet summers. It also has long, cold winters.

Figure: Gobi Desert.
The Gobi Desert is a cold desert ecosystem in northern China and southern Mongolia.

natural science

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

Solution: A cold desert is a type of ecosystem. Cold deserts have the following features: a small amount of rain or snow, dry, thin soil, and long, cold winters. So, the Gobi Desert has long, cold winters. It also has a small amount of rain or snow.


Question: Based on the map, which of the following areas did the Mongol Empire control?

Choices:
- South Asia
- Southeast Asia
- the Middle East

The Mongol Empire controlled most of Asia and some parts of Eastern Europe from around 1210 to 1375. Look at the map of the Mongol Empire. Then answer the question below.

social science

Solution:
Look back at the map. The labels on the map show the name of each region. The shaded area shows the territory controlled by the Mongol Empire.
The map shows that the Mongol Empire controlled many parts of Central Asia, East Asia, the Middle East, and Siberia.
The Mongol Empire did not control Southeast Asia or South Asia.


Question: Which continent is highlighted?

Choices:
- North America
- Africa
- Asia

social science

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

Solution: This continent is Asia.


Question: What is the capital of Oregon?

Choices:
- Portland
- Harrisburg
- Salem
- Carson City

social science

Solution: Salem is the capital of Oregon.


Question: Based on the text, how are fruit bats different from most other animals?

Choices:
- They can communicate with many kinds of animals.
- They can communicate about specific problems.
- They can understand some human speech.

Read the text about bats.
Several kinds of animals "talk" to one another in the wild. Dolphins whistle, birds sing, and wolves howl. In recent years, researchers have paid more attention to animal "languages," and they have made some surprising discoveries. Egyptian fruit bats, for example, have a very complex way of talking to one another. In fact, they are one of the few animals that direct their calls to another individual. Most animals make calls to their entire group. Bats can also share more complex information than other animals. This is because they have special sounds to communicate specific issues.
Researchers at Tel Aviv University in Israel wanted to learn more about what bats are really saying to one another. First, scientist Yossi Yovel and his team recorded sound and video of twenty-two bats. Fifteen thousand bat calls were collected over a period of seventy-five days. Then, the researchers tried to match each bat call with a behavior. They used special software to help them tell different bat calls apart and decipher the bats' messages.
What Yovel and his team found was astonishing. Egyptian fruit bats are not just making squeaky noises; they are expressing very distinct concerns. One type of call means the bats are arguing over food. Another type of call means the bats are figuring out where they are going to sleep. A third call is used when one bat has gotten too close to another.
The researchers made another startling discovery. A bat can alter the sound of its call when addressing different members of the group. This is similar to how humans may use a different tone of voice when speaking to different people. It turns out that bats use language as a way to communicate their needs to each other, almost like humans do.

language science

Solution:
These are two ways in which fruit bats are different from most other animals:
They can "talk" directly to one other fruit bat.
The first paragraph states that Egyptian fruit bats are one of the few species that will direct calls to another individual.
They can communicate about specific problems.
The first paragraph also states that bats have special sounds for talking about specific issues.
These things are not stated in the text:
They can communicate with many kinds of animals.
They can understand some human speech.


Question: What is the capital of Massachusetts?

Choices:
- Helena
- Cambridge
- Plymouth
- Boston

social science

Identify state capitals of the Northeast

Solution: Boston is the capital of Massachusetts.


Question: Which country is highlighted?

Choices:
- Solomon Islands
- Samoa
- Australia
- the Federated States of Micronesia

social science

Identify and select countries of Oceania

Solution: This country is the Federated States of Micronesia.


Question: Which of these states is farthest east?

Choices:
- Georgia
- North Dakota
- Oklahoma
- Louisiana

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 east arrow is pointing. Georgia is farthest east.


Question: Which property matches this object?

Choices:
- soft
- bouncy

natural science

An object has different properties. A property of an object can tell you how it looks, feels, tastes, or smells. Properties can also tell you how an object will behave when something happens to it.

Solution:
Look at the object.
Think about each property.
A bouncy object will bounce back from the floor if you drop it. The towel is not bouncy.
A soft object changes shape when pressed or squeezed. The towel is soft.


Question: Select the organism in the same genus as the great gray owl.

Choices:
- Cyanocitta stelleri
- Strix aluco
- Cyanocitta cristata

This organism is a great gray owl. Its scientific name is Strix nebulosa.

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 gray owl's scientific name is Strix nebulosa. The first word of its scientific name is Strix.
Cyanocitta stelleri is in the genus Cyanocitta. The first word of its scientific name is Cyanocitta. So, Cyanocitta stelleri and Strix nebulosa are not in the same genus.
Strix aluco is in the genus Strix. The first word of its scientific name is Strix. So, Strix aluco and Strix nebulosa are in the same genus.
Cyanocitta cristata is in the genus Cyanocitta. The first word of its scientific name is Cyanocitta. So, Cyanocitta cristata and Strix nebulosa are not in the same genus.


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

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

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

natural science

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

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


Question: Which of the following fossils is older? Select the more likely answer.

Choices:
- insect
- ginkgo leaf

This diagram shows fossils in an undisturbed sedimentary rock sequence.

natural science

Compare ages of fossils in a rock sequence

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

Solution:
Look again at the fossils in the rock sequence diagram.
Compare the positions of these fossils to determine which one is older:
The ginkgo leaf fossil is in a deeper layer in the rock sequence than the insect fossil. So, the ginkgo leaf fossil is most likely older than the insect fossil.


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

Choices:
- lichen katydid
- sharpnose-puffer

Golden dart frogs have poisonous glands in their brightly colored skin. The bright color serves as a warning sign that the animal is poisonous. The 's skin is adapted to ward off predators.
Figure: golden dart frog.

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 golden dart frog.
The golden dart frog has poisonous glands in its brightly colored skin. Its skin is adapted to ward off predators. The bright colors serve as a warning sign that the golden dart frog is poisonous.
Now look at each animal. Figure out which animal has a similar adaptation.
The sharpnose-puffer has a poisonous body with brightly colored skin. Its skin is adapted to ward off predators.
The lichen katydid has green and white patches on its body. Its skin is not adapted to be a warning sign that wards off predators.


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

The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material, 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:
The magnets in Pair 1 attract. The magnets in Pair 2 repel. But whether the magnets attract or repel affects only the direction of the magnetic force. It does not affect the magnitude of the magnetic force.
Magnet sizes affect the magnitude of the magnetic force. Imagine magnets that are the same shape and made of the same material. The larger the magnets, the greater the magnitude of the magnetic force between them.
Magnet A is the same size in both pairs. But Magnet B is larger in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is greater in Pair 2 than in Pair 1.


Question: In this food chain, the katydid is a primary consumer. Why?

Choices:
- It eats a primary consumer.
- It makes its own food.
- It eats a producer.

This diagram shows a food chain from a grassland ecosystem in Wyoming.

natural science

Every organism needs food to stay alive. Organisms get their food in different ways. A food chain shows how organisms in an ecosystem get their food.
The food chain begins with the producer. A producer can change matter that is not food into food. Many producers use carbon dioxide, water, and sunlight to make sugar. Carbon dioxide and water are not food, but sugar is food for the producer.
Consumers eat other organisms. There can be several kinds of consumers in a food chain:
A primary consumer eats producers. The word primary tells you that this is the first consumer in a food chain.
A secondary consumer eats primary consumers. The word secondary tells you that this is the second consumer in a food chain.
A tertiary consumer eats secondary consumers. The word tertiary tells you that this is the third consumer in a food chain.
A top consumer is the animal at the top of a food chain. Food chains can have different numbers of organisms. For example, when there are four organisms in the chain, the top consumer is the tertiary consumer. But if there are five organisms in the chain, the top consumer eats the tertiary consumer!

Solution: In this food chain, the katydid is a primary consumer because it eats a producer. The producer in this food chain is the slender wheatgrass.


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 greater in Pair 1.
- 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.

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:
The magnets in Pair 2 attract. The magnets in Pair 1 repel. But whether the magnets attract or repel affects only the direction of the magnetic force. It does not affect the magnitude of the magnetic force.
Magnet sizes affect the magnitude of the magnetic force. Imagine magnets that are the same shape and made of the same material. The 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: What is the probability that a Labrador retriever produced by this cross will have brown fur?

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

In a group of Labrador retrievers, some individuals have black fur and others have brown fur. In this group, the gene for the fur color trait has two alleles. The allele for black fur (F) is dominant over the allele for brown fur (f).
This Punnett square shows a cross between two Labrador retrievers.

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 is the main persuasive appeal used in this ad?

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

language science

Identify appeals to ethos, pathos, and logos in advertisements

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

Solution: The ad appeals to logos, or reason. It uses a specific point of comparison (the amount of iron in one ounce).


Question: Is plagioclase a mineral?

Choices:
- no
- yes

Plagioclase has the following properties:
found in nature
solid
not made by living things
pure substance
fixed crystal structure

natural science

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

Solution: Plagioclase has all the properties of a mineral. So, plagioclase is a mineral.


Question: What is the name of the colony shown?

Choices:
- Maryland
- Massachusetts
- Illinois
- Connecticut

social science

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


Question: What is the capital of Rhode Island?

Choices:
- Hartford
- Newport
- Providence
- Tulsa

social science

Identify state capitals of the Northeast

Solution: Providence is the capital of Rhode Island.


Question: Which ocean is highlighted?

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

social science

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

Solution: This is the Atlantic Ocean.