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Compare the average kinetic energies of the particles in each sample. Which sample has the higher temperature?
[ "sample B", "neither; the samples have the same temperature", "sample A" ]
0
The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.
closed choice
grade6
natural science
physics
Particle motion and energy
Identify how particle motion affects temperature and pressure
The temperature of a substance depends on the average kinetic energy of the particles in the substance. The higher the average kinetic energy of the particles, the higher the temperature of the substance. The kinetic energy of a particle is determined by its mass and speed. For a pure substance, the greater the mass of each particle in the substance and the higher the average speed of the particles, the higher their average kinetic energy.
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.
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Using only these supplies, which question can Martha investigate with an experiment?
[ "Does the basketball bounce higher on gravel or on grass?", "Do larger basketballs bounce higher than smaller basketballs on a brick patio?", "Does the basketball bounce higher on a lawn or on a dirt path?" ]
0
Martha gets a basketball for her birthday and dribbles it around her neighborhood. She notices that sometimes the ball bounces higher than other times. She wonders what factors affect how high her ball bounces. So, she decides to design an experiment. She has the following supplies available: one basketball access to a brick patio access to a grassy lawn access to a gravel driveway a meterstick
closed choice
grade6
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
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Select the animal that does not have a backbone.
[ "toucan", "castor bean tick" ]
1
Hint: Insects, spiders, and worms do not have backbones.
closed choice
grade2
natural science
biology
Classification
Identify animals with and without backbones
Some animals have a backbone. The backbone is made of many bones in an animal's back. An animal's backbone helps connect the different parts of its body. In the drawings below, each animal's backbone is colored orange. Other animals do not have a backbone. In fact, these animals don't have any bones! Some animals without backbones have a hard outer cover. Other animals have a soft body.
A castor bean tick is an insect. Like other insects, a castor bean tick does not have a backbone. It has a hard outer cover. A toucan is a bird. Like other birds, a toucan has a backbone.
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Based on this information, what is Sugar's phenotype for the fur texture trait?
[ "straight fur", "wavy fur" ]
1
In a group of Syrian hamsters, some individuals have straight fur and others have wavy fur. In this group, the gene for the fur texture trait has two alleles. The allele for wavy fur (f) is recessive to the allele for straight fur (F). Sugar is a Syrian hamster from this group. Sugar has the homozygous genotype ff for the fur texture gene.
closed choice
grade8
natural science
biology
Genes to traits
Genetics vocabulary: dominant and recessive
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait. Some traits, like flower color in pea plants, are controlled by a single gene. Most plants and animals have a genotype made up of two alleles for these traits. These two alleles determine whether an organism is homozygous or heterozygous for the gene. An organism with two identical alleles for a gene is homozygous for that gene. A pea plant with the genotype FF or ff is homozygous for the flower color gene. An organism with two different alleles for a gene is heterozygous for that gene. A pea plant with the genotype Ff is heterozygous for the flower color gene. The types of alleles in an organism's genotype determine the organism's phenotype. Some alleles have types called dominant and recessive. These two types can cause different versions of a trait to appear as the organism's phenotype. A dominant allele causes its version of the trait to appear even when the organism also has a recessive allele for the gene. In pea plants, the F allele, which causes purple flowers, is dominant over the f allele. A pea plant with at least one F allele will have the F allele's version of the flower color trait. So, a plant with the genotype FF or Ff will have purple flowers. A recessive allele causes its version of the trait to appear only when the organism does not have any dominant alleles for the gene. In pea plants, the f allele, which causes white flowers, is recessive to the F allele. A pea plant with only f alleles will have the f allele's version of the flower color trait. So, a plant with the genotype ff will have white flowers.
Sugar's genotype for the fur texture gene is ff. Sugar's genotype of ff has only f alleles. The f allele is for wavy fur. So, Sugar's phenotype for the fur texture trait must be wavy fur. To check this answer, consider whether Sugar's alleles are dominant or recessive. The allele for wavy fur (f) is recessive to the allele for straight fur (F). This means F is a dominant allele, and f is a recessive allele. Sugar's genotype of ff has only recessive alleles. An organism with only recessive alleles for a gene will have the recessive allele's version of the trait. So, Sugar's phenotype for the fur texture trait must be wavy fur.
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What is the source of the allusion in the sentence below? The politician's staff decided it was time to get off the Titanic, so they left the campaign and started looking for other jobs.
[ "history", "a song" ]
0
closed choice
grade9
language science
figurative-language
Literary devices
Recall the source of an allusion
An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words. "I'd better get home before I turn into a pumpkin!" Lila remarked. Here, Lila alludes to the fairy tale "Cinderella," in which Cinderella must leave the ball before the coach that brought her transforms into a pumpkin. The allusion shows that Lila must depart immediately.
The source of the allusion Titanic is history. The Titanic was a luxury steamship touted as indestructible, but in 1912, on its maiden voyage, it hit an iceberg in the Atlantic Ocean and sank. The allusion Titanic means a large project facing failure.
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Which logical fallacy is used in the text? Does she do well in school because she's smart, or is it because she works hard?
[ "slippery slope fallacy: the false assumption that a small first step will lead to extreme consequences", "ad hominem: an attack against the person making the argument, rather than the argument itself", "false dichotomy: an argument that presents only two choices when more options exist" ]
2
closed choice
grade10
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fallacy may present irrelevant information: Fallacy | Description ad hominem | an attack against the person making the argument, rather than the argument itself appeal to nature | an argument that assumes the natural choice is always the best choice bandwagon fallacy | an argument that assumes the popular choice is always the best choice circular reasoning | an argument that supports a claim with the claim itself guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something A logical fallacy may misrepresent the issues at hand: Fallacy | Description false causation | the assumption that because two things happened together, one caused the other false dichotomy | an argument that presents only two choices when more options exist hasty generalization | a broad claim based on too few observations slippery slope fallacy | the false assumption that a small first step will necessarily lead to extreme consequences straw man | a misrepresentation of an opponent's position that makes it easier to argue against
The text argues that she must do well in school either because she's smart or because she works hard. However, someone can be both smart and hardworking. This illustrates a type of logical fallacy known as a false dichotomy.
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Use the evidence in the text to select the photosynthetic organism.
[ "The Sargasso Sea in the Atlantic Ocean is named after Sargassum algae. This organism floats on the surface of tropical waters and uses energy from sunlight to make food.", "The shaggy frogfish is able to blend into its surroundings because it looks like a rock covered in algae. The shaggy frogfish also has a small, white fin on its head that it uses to attract other fish. The frogfish can eat these fish in one gulp." ]
0
closed choice
grade7
natural science
biology
Photosynthesis
Identify the photosynthetic organism
Organisms that carry out photosynthesis are called photosynthetic organisms. During photosynthesis, these organisms use light energy, carbon dioxide, and water to produce sugars and oxygen. Photosynthetic organisms also often have the following characteristics: They are producers, which are organisms that make their own food inside their cells. Because producers make their own food, they typically do not eat other organisms. Their cells contain chloroplasts, which are cell structures where photosynthesis occurs. Their chloroplasts often contain a green substance called chlorophyll. Chlorophyll captures light energy from the Sun to power photosynthesis. They use the sugars they produce during photosynthesis as food. This food provides energy that helps the organisms live, grow, and reproduce.
This organism is photosynthetic: The text tells you that Sargassum algae uses energy from sunlight to make food. This is evidence that Sargassum algae is a photosynthetic organism. This organism is not photosynthetic: The text does not provide evidence that the shaggy frogfish is photosynthetic.
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Which of the following contains a vague pronoun reference?
[ "Danny peeled the wrappers off of the blueberry muffins and then set them aside.", "Danny peeled the wrappers off of the blueberry muffins and then set the wrappers aside." ]
0
closed choice
grade7
language science
writing-strategies
Pronouns and antecedents
Identify vague pronoun references
When writing, make sure to avoid vague pronoun references. A vague pronoun reference occurs when a pronoun could refer to more than one possible antecedent. When Lisa and Kim finally landed, she breathed a sigh of relief. The pronoun she could refer to either Lisa or Kim, so the meaning of the sentence is unclear. Vague pronoun references can be corrected in one of two ways: 1. Replace the pronoun with its correct antecedent: When Lisa and Kim finally landed, Lisa breathed a sigh of relief. 2. Rewrite the sentence: Lisa breathed a sigh of relief when she and Kim finally landed. A vague pronoun reference also occurs when they, them, their, theirs, it, or its is used without its antecedent. They say that this nail polish dries in less than five minutes. The pronoun they is used without its antecedent, so the meaning of the sentence is unclear. This problem can be fixed by replacing the pronoun with its missing antecedent. The advertisements say that this nail polish dries in less than five minutes.
The second answer choice contains a vague pronoun reference. The pronoun them could refer to the wrappers or the blueberry muffins. The first answer choice shows a possible correction for the vague pronoun reference. Them has been replaced with the wrappers. Danny peeled the wrappers off of the blueberry muffins and then set the wrappers aside.
Based on the event chain, which event leads directly to the defeat of the loon's team?
[ "The Winter Wind joins the hawk's team.", "A goose joins the loon's team." ]
0
This event chain shows the events from an Ojibwe legend.
closed choice
grade6
language science
writing-strategies
Visual elements
Read graphic organizers
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.
An event chain uses arrows to show the order of events. This event chain shows the events from an Ojibwe legend. Follow the arrows to see the order of events. Find the box that says The loon's team is quickly defeated. The event The Winter Wind comes and joins the hawk's team comes directly before this in the event chain. This tells you that the event The Winter Wind joins the hawk's team directly leads to the defeat of the loon's team.
What can Gavin and Nolan trade to each get what they want?
[ "Nolan can trade his broccoli for Gavin's oranges.", "Nolan can trade his almonds for Gavin's tomatoes.", "Gavin can trade his tomatoes for Nolan's broccoli.", "Gavin can trade his tomatoes for Nolan's sandwich." ]
2
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. Gavin and Nolan open their lunch boxes in the school cafeteria. Both of them could be happier with their lunches. Gavin wanted broccoli in his lunch and Nolan was hoping for tomatoes. Look at the images of their lunches. Then answer the question below.
closed choice
grade6
social science
economics
Basic economic principles
Trade and specialization
Gavin wanted broccoli in his lunch and Nolan was hoping for tomatoes. Look at the labeled part of the images. Gavin has tomatoes. Nolan has broccoli. They can trade tomatoes for broccoli to both be happier. Trading other things would not help either person get more items they want.
Which animal is also adapted to be camouflaged among dead leaves?
[ "skunk", "fantastic leaf-tailed gecko" ]
1
Dead leaf mantises are found in forests. The mantis is adapted to be camouflaged among dead leaves. Figure: dead leaf mantis.
closed choice
grade5
natural science
biology
Adaptations
Animal adaptations: skins and body coverings
An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The color, texture, and covering of an animal's skin are examples of adaptations. Animals' skins can be adapted in different ways. For example, skin with thick fur might help an animal stay warm. Skin with sharp spines might help an animal defend itself against predators.
Look at the picture of the dead leaf mantis. The dead leaf mantis has a reddish-brown body. It is adapted to be camouflaged among dead leaves, which often have a reddish or brownish color. The word camouflage means to blend in. Now look at each animal. Figure out which animal has a similar adaptation. The fantastic leaf-tailed gecko has reddish-brown skin and a leaf-shaped tail. It is adapted to be camouflaged among dead leaves, which often have a reddish or brownish color. The skunk has black-and-white fur covering its body. It is not adapted to be camouflaged among dead leaves.
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What does the simile in this text suggest? A simple change of scenery can be like an ice-cold lemonade on a warm summer day.
[ "Spending time in a different place is refreshing.", "A cold climate is invigorating." ]
0
closed choice
grade10
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. A simile uses like or as to compare two things that are not actually alike. The cat's fur was as dark as the night.
The text includes a simile, using like or as to compare two things that are not actually alike. The simile like an ice-cold lemonade suggests that spending time in a different place is refreshing. An ice-cold lemonade can make you feel better, and so can a change of scenery.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnitude of the magnetic force is smaller in Pair 2.", "The magnitude of the magnetic force is smaller in Pair 1.", "The magnitude of the magnetic force is the same in both pairs." ]
2
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade8
natural science
physics
Velocity, acceleration, and forces
Compare magnitudes of magnetic forces
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other.
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. 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.
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Which text uses the word disinterested in its traditional sense?
[ "Bonnie is excellent in her position as class treasurer. She always manages to be disinterested in student council debates about the allocation of extracurricular funds.", "Bonnie is happy with her position as class treasurer. Though she would have the support of the student council, she is disinterested in running for student body president." ]
0
closed choice
grade9
language science
writing-strategies
Word usage and nuance
Explore words with new or contested usages
Words change in meaning when speakers begin using them in new ways. For example, the word peruse once only meant to examine in detail, but it's now also commonly used to mean to look through in a casual manner. When a word changes in meaning, its correct usage is often debated. Although a newer sense of the word may be more commonly used, many people consider a word's traditional definition to be the correct usage. Being able to distinguish the different uses of a word can help you use it appropriately for different audiences. Britney perused her notes, carefully preparing for her exam. The traditional usage above is considered more standard. David perused the magazine, absentmindedly flipping through the pages. The nontraditional usage above is now commonly used, but traditional style guides generally advise against it.
The second text uses disinterested in its traditional sense: unbiased or impartial. Bonnie is excellent in her position as class treasurer. She always manages to be disinterested in student council debates about the allocation of extracurricular funds. The first text uses disinterested in its nontraditional sense: uninterested or indifferent. Bonnie is happy with her position as class treasurer. Though she would have the support of the student council, she is disinterested in running for student body president. Most style guides recommend to use the traditional sense of the word disinterested because it is considered more standard.
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What information supports the conclusion that Scott acquired this trait?
[ "Scott learned how to build a fire at summer camp.", "Scott can cook food over a fire." ]
0
Read the description of a trait. Scott knows how to build a fire.
closed choice
grade3
natural science
biology
Heredity
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment.
Which of the following organisms is the secondary consumer in this food web?
[ "zooplankton", "phytoplankton", "kelp", "plainfin midshipman" ]
3
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.
closed choice
grade8
natural science
biology
Ecological interactions
Interpret food webs I
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.
Secondary consumers eat primary consumers, and primary consumers eat producers. So, in a food web, secondary consumers have arrows pointing to them from primary consumers. Primary consumers have arrows pointing to them from producers. The zooplankton has an arrow pointing to it from the phytoplankton. The phytoplankton is not a primary consumer. So, the zooplankton is not a secondary consumer. The kelp does not have any arrows pointing to it. So, the kelp is not a secondary consumer. The kelp bass has arrows pointing to it from the zooplankton and the plainfin midshipman. The zooplankton and the plainfin midshipman are primary consumers, so the kelp bass is a secondary consumer. The phytoplankton does not have any arrows pointing to it. So, the phytoplankton is not a secondary consumer. The plainfin midshipman has an arrow pointing to it from the zooplankton. The zooplankton is a primary consumer, so the plainfin midshipman is a secondary consumer.
Which i in column 1?
[ "the fast-food restaurant", "the police department", "the grocery store", "the fire department" ]
3
closed choice
grade3
social science
geography
Geography
Use a letter-number grid
A grid is made up of lines of squares. They are organized in rows and columns. A grid can help you use a map. A row is a line of squares that goes from side to side. Rows are marked with letters. A column is a line of squares that goes up and down. Columns are marked with numbers.
The fire department is in column 1.
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What is the mass of a news magazine?
[ "9 tons", "9 pounds", "9 ounces" ]
2
Select the best estimate.
closed choice
grade5
natural science
units-and-measurement
Units and measurement
Choose customary units of mass
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Mass is a measurement of how much matter something contains. There are many different units of mass. When you are using customary units, mass may be written with units of ounces, pounds, or tons. There are 16 ounces in 1 pound and 2,000 pounds in 1 ton. So, 1 ounce is less than 1 pound and much less than 1 ton. A slice of bread has a mass of about 1 ounce, while a can of beans has a mass of about 1 pound. A small car has a mass of about 1 ton.
The best estimate for the mass of a news magazine is 9 ounces. 9 pounds and 9 tons are both too heavy.
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Which correctly shows the title of a movie?
[ "The Princess and the Frog", "The princess and the Frog" ]
0
closed choice
grade4
language science
capitalization
Formatting
Capitalizing titles
In a title, capitalize the first word, the last word, and every important word in between. The Wind in the Willows James and the Giant Peach These words are not important in titles: Articles, a, an, the Short prepositions, such as at, by, for, in, of, on, to, up Coordinating conjunctions, such as and, but, or
Capitalize the first word, the last word, and every important word in between. The words and and the are not important, so they should not be capitalized. The correct title is The Princess and the Frog.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The strength of the magnetic force is the same in both pairs.", "The magnetic force is stronger in Pair 2.", "The magnetic force is stronger in Pair 1." ]
2
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade4
natural science
physics
Magnets
Compare strengths of magnetic forces
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The stronger the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the strength of a magnetic force between two magnets by changing the distance between them. The magnetic force is stronger when the magnets are closer together.
Distance affects the strength of the magnetic force. When magnets are closer together, the magnetic force between them is stronger. The magnets in Pair 1 are closer together than the magnets in Pair 2. So, the magnetic force is stronger in Pair 1 than in Pair 2.
Which animal's feet are also adapted for sticking to smooth surfaces?
[ "meerkat", "Madagascar day gecko" ]
1
s live in the rain forests of Indonesia. They spend most of their lives in trees. The feet of the are adapted to stick to the smooth surfaces of leaves. Figure: Borneo eared frog.
closed choice
grade4
natural science
biology
Adaptations
Animal adaptations: feet and limbs
An adaptation is an inherited trait that helps an organism survive or reproduce. Adaptations can include both body parts and behaviors. The shape of an animal's feet is one example of an adaptation. Animals' feet can be adapted in different ways. For example, webbed feet might help an animal swim. Feet with thick fur might help an animal walk on cold, snowy ground.
Look at the picture of the Borneo eared frog. The Borneo eared frog has wide, sticky toes. Its feet are adapted for sticking to smooth surfaces. The Borneo eared frog uses its toes to walk on the smooth surfaces of leaves without slipping. Now look at each animal. Figure out which animal has a similar adaptation. The Madagascar day gecko has wide, sticky toes. Its feet are adapted for sticking to smooth surfaces. The meerkat has long claws on its toes. Its feet are not adapted for sticking to smooth surfaces. The meerkat uses its feet to dig burrows and search for food.
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Which tense does the sentence use? Katie and Liz race down the hill.
[ "present tense", "future tense", "past tense" ]
0
closed choice
grade2
language science
verbs
Verb tense
Is the sentence in the past, present, or future tense?
Present tense verbs tell you about something that is happening now. Most present-tense verbs are regular. They have no ending, or they end in -s or -es. Two verbs are irregular in the present tense, to be and to have. You must remember their forms. Past tense verbs tell you about something that has already happened. Most past-tense verbs are regular. They end in -ed. Some verbs are irregular in the past tense. You must remember their past-tense forms. Future tense verbs tell you about something that is going to happen. All future-tense verbs use the word will. Present | Past | Future walk, walks | walked | will walk go, goes | went | will go
The sentence is in present tense. You can tell because it uses a present-tense verb, race. The verb tells you about something that is true or happening now.
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Which block of iron has more thermal energy?
[ "the hotter block of iron", "the colder block of iron" ]
0
Two 1-kilogram blocks of iron are identical except for their temperatures.
closed choice
grade5
natural science
physics
Heat and thermal energy
How are temperature and mass related to thermal energy?
Matter is made of tiny particles called atoms. Atoms are always moving. The energy of moving atoms is called thermal energy. The total amount of thermal energy in matter depends on three things: the type of matter, the amount of matter, and how fast the atoms are moving. Temperature measures how hot or cold matter is. If the atoms in matter move faster, the temperature goes up. The matter now has both more thermal energy and a higher temperature. What happens if the amount of matter changes? A 2-kilogram brick at 70°F has twice as much thermal energy as a 1-kilogram brick at 70°F. The two bricks have the same temperature, but the larger brick has twice as many atoms. So, it has twice as much thermal energy.
The two blocks of iron are made of the same material and have the same mass. So, the hotter block of iron has more thermal energy.
Complete the text to describe the diagram. Solute particles moved in both directions across the permeable membrane. But more solute particles moved across the membrane (). When there was an equal concentration on both sides, the particles reached equilibrium.
[ "to the left than to the right", "to the right than to the left" ]
0
The diagram below shows a solution with one solute. Each solute particle is represented by a green ball. The solution fills a closed container that is divided in half by a membrane. The membrane, represented by a dotted line, is permeable to the solute particles. The diagram shows how the solution can change over time during the process of diffusion.
closed choice
grade6
natural science
chemistry
Solutions
Diffusion across membranes
In a solution, solute particles move and spread throughout the solvent. The diagram below shows how a solution can change over time. Solute particles move from the area where they are at a higher concentration to the area where they are at a lower concentration. This movement happens through the process of diffusion. As a result of diffusion, the concentration of solute particles becomes equal throughout the solution. When this happens, the solute particles reach equilibrium. At equilibrium, the solute particles do not stop moving. But their concentration throughout the solution stays the same. Membranes, or thin boundaries, can divide solutions into parts. A membrane is permeable to a solute when particles of the solute can pass through gaps in the membrane. In this case, solute particles can move freely across the membrane from one side to the other. So, for the solute particles to reach equilibrium, more particles will move across a permeable membrane from the side with a higher concentration of solute particles to the side with a lower concentration. At equilibrium, the concentration on both sides of the membrane is equal.
Look at the diagram again. It shows you how the solution changed during the process of diffusion. Before the solute particles reached equilibrium, there were 2 solute particles on the left side of the membrane and 6 solute particles on the right side of the membrane. When the solute particles reached equilibrium, there were 4 solute particles on each side of the membrane. There were 2 more solute particles on the left side of the membrane than before. So, for the solute particles to reach equilibrium, more solute particles must have moved across the membrane to the left than to the right.
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Using only these supplies, which question can Dan investigate with an experiment?
[ "Do toy cars go faster down the ramp made of wood or the ramp made of cardboard?", "Do toy cars with plastic wheels go faster down the cardboard ramp than toy cars with metal wheels?", "Does a big toy car go down the wooden ramp faster than a small toy car?" ]
0
Dan and his sister are building ramps to race their toy cars down. Dan notices that the cars go down some of the ramps faster than others. He wonders what factors affect the cars' speed. So, he decides to design an experiment. He has the following supplies available: two identical toy cars a wooden ramp three feet long and two feet tall a cardboard ramp three feet long and two feet tall
closed choice
grade6
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
Complete the text to describe the diagram. Solute particles moved in both directions across the permeable membrane. But more solute particles moved across the membrane (). When there was an equal concentration on both sides, the particles reached equilibrium.
[ "to the right than to the left", "to the left than to the right" ]
1
The diagram below shows a solution with one solute. Each solute particle is represented by a green ball. The solution fills a closed container that is divided in half by a membrane. The membrane, represented by a dotted line, is permeable to the solute particles. The diagram shows how the solution can change over time during the process of diffusion.
closed choice
grade6
natural science
chemistry
Solutions
Diffusion across membranes
In a solution, solute particles move and spread throughout the solvent. The diagram below shows how a solution can change over time. Solute particles move from the area where they are at a higher concentration to the area where they are at a lower concentration. This movement happens through the process of diffusion. As a result of diffusion, the concentration of solute particles becomes equal throughout the solution. When this happens, the solute particles reach equilibrium. At equilibrium, the solute particles do not stop moving. But their concentration throughout the solution stays the same. Membranes, or thin boundaries, can divide solutions into parts. A membrane is permeable to a solute when particles of the solute can pass through gaps in the membrane. In this case, solute particles can move freely across the membrane from one side to the other. So, for the solute particles to reach equilibrium, more particles will move across a permeable membrane from the side with a higher concentration of solute particles to the side with a lower concentration. At equilibrium, the concentration on both sides of the membrane is equal.
Look at the diagram again. It shows you how the solution changed during the process of diffusion. Before the solute particles reached equilibrium, there were 3 solute particles on the left side of the membrane and 7 solute particles on the right side of the membrane. When the solute particles reached equilibrium, there were 5 solute particles on each side of the membrane. There were 2 more solute particles on the left side of the membrane than before. So, for the solute particles to reach equilibrium, more solute particles must have moved across the membrane to the left than to the right.
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Select the mixture.
[ "silver", "pasta sauce" ]
1
closed choice
grade2
natural science
physics
Mixtures
Identify mixtures
A pure substance is made of only one type of matter. A mixture is made of two or more types of matter mixed together.
In this food chain, the wild oat is a producer. Why?
[ "It eats another organism.", "It makes its own food." ]
1
This diagram shows a food chain from a grassland ecosystem in Wyoming.
closed choice
grade4
natural science
biology
Ecosystems
Identify roles in food chains
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.
In this food chain, the wild oat is a producer because it makes its own food. The wild oat uses carbon dioxide, water, and sunlight to make its own food.
What is the capital of Georgia?
[ "Atlanta", "Topeka", "Athens", "Savannah" ]
0
closed choice
grade3
social science
geography
State capitals
Identify state capitals of the Southeast
Atlanta is the capital of Georgia.
Which better describes the Bering Land Bridge National Preserve ecosystem?
[ "It has long, cold winters. It also has many evergreen trees.", "It has mostly small plants. It also has short, cold summers." ]
1
Figure: Bering Land Bridge National Preserve. Bering Land Bridge National Preserve is a tundra ecosystem in western Alaska.
closed choice
grade4
natural science
biology
Ecosystems
Describe ecosystems
An environment includes all of the biotic, or living, and abiotic, or nonliving, things in an area. An ecosystem is created by the relationships that form among the biotic and abiotic parts of an environment. There are many different types of terrestrial, or land-based, ecosystems. Here are some ways in which terrestrial ecosystems can differ from each other: the pattern of weather, or climate the type of soil the organisms that live there
A tundra is a type of ecosystem. Tundras have the following features: long, cold winters and short, cold summers, soil that is frozen year-round, and mostly small plants. So, Bering Land Bridge National Preserve has mostly small plants. It also has short, cold summers.
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Which logical fallacy is used in the text? Jackson is not qualified to run the Environmental Club. Have you seen his sister's huge, horrifically inefficient car? The planet cries whenever she turns on the ignition.
[ "slippery slope fallacy: the false assumption that a small first step will lead to extreme consequences", "guilt by association: a negative association intended to discredit someone or something", "straw man: a misrepresentation of an opponent's position that makes it easier to argue against" ]
1
closed choice
grade9
language science
writing-strategies
Developing and supporting arguments
Classify logical fallacies
A strong argument uses valid reasoning and logic in support of a claim. When an argument or claim introduces irrelevant information or misrepresents the issues at hand, it may be committing a logical fallacy. Logical fallacies can hurt a writer's credibility and can lead readers to draw false conclusions. A logical fallacy may present irrelevant information: Fallacy | Description ad hominem | an attack against the person making the argument, rather than the argument itself appeal to nature | an argument that assumes the natural choice is always the best choice bandwagon fallacy | an argument that assumes the popular choice is always the best choice circular reasoning | an argument that supports a claim with the claim itself guilt by association | an unfair negative association with another person or group that is intended to discredit someone or something A logical fallacy may misrepresent the issues at hand: Fallacy | Description false causation | the assumption that because two things happened together, one caused the other false dichotomy | an argument that presents only two choices when more options exist hasty generalization | a broad claim based on too few observations slippery slope fallacy | the false assumption that a small first step will necessarily lead to extreme consequences straw man | a misrepresentation of an opponent's position that makes it easier to argue against
The text argues that Jackson isn't qualified to run the Environmental Club because his sister drives a fuel inefficient car. However, the behavior of Jackson's sister does not necessarily reflect Jackson's own behavior. This illustrates a type of logical fallacy known as guilt by association.
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Which is a complex sentence?
[ "Freedom of speech and trial by jury are two important rights in the United States Constitution.", "Kyle picked raspberries in the field until his fingertips were stained red." ]
1
closed choice
grade6
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple, compound, or complex?
A clause is a group of words that contains both a subject and a predicate. An independent clause is a complete thought. It can stand alone as a sentence. A dependent clause is not a complete thought. It cannot stand alone as a sentence. the oranges on our tree are ripe The clause can stand alone. It is independent. after we pick up Kevin from work The clause cannot stand alone. It is dependent. A simple sentence is made up of a single independent clause. Ben and I spent all day relaxing by the pool. Some simple sentences have introductory phrases, but the introductory phrase is part of the predicate. In the winter, Ben usually wears his heavy coat. Ben usually wears his heavy coat in the winter. A compound sentence is made up of two independent clauses joined by a coordinating conjunction such as and, but, or, or so. We saw a flash of lightning, and seconds later we heard the rumble of thunder. A complex sentence is made up of an independent clause and a dependent clause. The dependent clause usually begins with a subordinating conjunction such as after, although, as, because, before, if, since, unless, until, when, or while. If she ever gets the chance, Terri would love to visit the Egyptian pyramids.
The second sentence is the complex sentence. It is made up of an independent clause and a dependent clause. The dependent clause begins with the subordinating conjunction until. Kyle picked raspberries in the field until his fingertips were stained red.
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Which is the most flexible?
[ "cardboard", "brick path", "wood board" ]
0
closed choice
grade4
natural science
physics
Materials
Compare properties of materials
Every object is made of one or more materials. A material is a type of matter. Wood, glass, metal, and plastic are common materials. A material has different properties. A material's properties tell you how it looks, feels, tastes, or smells. Some examples of properties are shiny, hard, fragile, and stretchy. For example, a shiny material reflects a lot of light. A fragile material breaks when you drop it.
Flexible is a property. A flexible material can be bent without breaking easily. Look at each picture, one at a time. Imagine bending the material shown in each picture. Of the choices, the cardboard is the most flexible. If you gently twist cardboard, it will not tear easily.
What is the capital of Mississippi?
[ "Jackson", "Raleigh", "Biloxi", "Tallahassee" ]
0
closed choice
grade5
social science
geography
State capitals
Identify state capitals of the Southeast
Jackson is the capital of Mississippi.
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Which organ controls what the body's organs do?
[ "skin", "lungs", "brain", "heart" ]
2
closed choice
grade4
natural science
biology
Animals
Human organs and their functions
What is the probability that a horse produced by this cross will be heterozygous for the coat color gene?
[ "2/4", "0/4", "1/4", "3/4", "4/4" ]
1
In a group of horses, some individuals have a black coat and others have a reddish-brown coat. In this group, the gene for the coat color trait has two alleles. The allele for a reddish-brown coat (l) is recessive to the allele for a black coat (L). This Punnett square shows a cross between two horses.
closed choice
grade8
natural science
biology
Genes to traits
Use Punnett squares to calculate probabilities of offspring types
Offspring genotypes: homozygous or heterozygous? How do you determine whether an organism is homozygous or heterozygous for a gene? Look at the alleles in the organism's genotype for that gene. An organism with two identical alleles for a gene is homozygous for that gene. If both alleles are dominant, the organism is homozygous dominant for the gene. If both alleles are recessive, the organism is homozygous recessive for the gene. An organism with two different alleles for a gene is heterozygous for that gene. In a Punnett square, each box represents a different outcome, or result. Each of the four outcomes is equally likely to happen. Each box represents one way the parents' alleles can combine to form an offspring's genotype. Because there are four boxes in the Punnett square, there are four possible outcomes. An event is a set of one or more outcomes. The probability of an event is a measure of how likely the event is to happen. This probability is a number between 0 and 1, and it can be written as a fraction: probability of an event = number of ways the event can happen / number of equally likely outcomes You can use a Punnett square to calculate the probability that a cross will produce certain offspring. For example, the Punnett square below has two boxes with the genotype Ff. It has one box with the genotype FF and one box with the genotype ff. This means there are two ways the parents' alleles can combine to form Ff. There is one way they can combine to form FF and one way they can combine to form ff. | F | f F | FF | Ff f | Ff | ff Consider an event in which this cross produces an offspring with the genotype ff. The probability of this event is given by the following fraction: number of ways the event can happen / number of equally likely outcomes = number of boxes with the genotype ff / total number of boxes = 1 / 4
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Using only these supplies, which question can Bryan investigate with an experiment?
[ "Which of the three types of tomato seeds sprouts the fastest?", "Does a certain kind of tomato plant grow taller when planted in a clay pot or in a plastic pot?", "Which type of soil will cause a certain kind of tomato plant to grow the most fruit?" ]
0
Bryan and his classmates are growing tomato plants in the school garden. He wonders what factors affect how tomato plants grow. So, he decides to design an experiment. He has the following supplies available: three different types of tomato seeds one bag of potting soil five identical clay pots water
closed choice
grade7
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
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Which pencil has a higher temperature?
[ "the pencil with more thermal energy", "the pencil with less thermal energy" ]
0
Two pencils are identical except for their thermal energies.
closed choice
grade6
natural science
physics
Thermal energy
How are temperature and mass related to thermal energy?
Matter is made of tiny particles called atoms. Atoms are always moving. The energy of moving atoms is called thermal energy. The total amount of thermal energy in matter depends on three things: the type of matter, the amount of matter, and how fast the atoms are moving. Temperature measures how hot or cold matter is. If the atoms in matter move faster, the temperature goes up. The matter now has both more thermal energy and a higher temperature. What happens if the amount of matter changes? A 2-kilogram brick at 70°F has twice as much thermal energy as a 1-kilogram brick at 70°F. The two bricks have the same temperature, but the larger brick has twice as many atoms. So, it has twice as much thermal energy.
The two pencils are made of the same material and have the same mass. So, the pencil with more thermal energy has a higher temperature.
Compare the average kinetic energies of the particles in each sample. Which sample has the higher temperature?
[ "sample B", "sample A", "neither; the samples have the same temperature" ]
1
The diagrams below show two pure samples of gas in identical closed, rigid containers. Each colored ball represents one gas particle. Both samples have the same number of particles.
closed choice
grade6
natural science
physics
Particle motion and energy
Identify how particle motion affects temperature and pressure
The temperature of a substance depends on the average kinetic energy of the particles in the substance. The higher the average kinetic energy of the particles, the higher the temperature of the substance. The kinetic energy of a particle is determined by its mass and speed. For a pure substance, the greater the mass of each particle in the substance and the higher the average speed of the particles, the higher their average kinetic energy.
Each particle in the two samples has the same mass, but the particles in sample A have a higher average speed than the particles in sample B. So, the particles in sample A have a higher average kinetic energy than the particles in sample B. Because the particles in sample A have the higher average kinetic energy, sample A must have the higher temperature.
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What information supports the conclusion that Whitney acquired this trait?
[ "Whitney learned how to build a fire at summer camp.", "Whitney can cook food over a fire." ]
0
Read the description of a trait. Whitney knows how to build a fire.
closed choice
grade6
natural science
biology
Genes to traits
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down from biological parents to their offspring through genes. Genes are pieces of hereditary material that contain the instructions that affect inherited traits. Offspring receive their genes, and therefore gain their inherited traits, from their biological parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment. Parents do not pass acquired traits down to their offspring.
What is the capital of Maryland?
[ "Harrisburg", "Augusta", "Norfolk", "Annapolis" ]
3
closed choice
grade5
social science
geography
State capitals
Identify state capitals of the Northeast
Annapolis is the capital of Maryland.
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Which sentence states a fact?
[ "In a beehive, a worker bee's job is more important than the queen's job.", "In a beehive, the queen lays eggs while the workers guard the hive." ]
1
closed choice
grade3
language science
writing-strategies
Opinion writing
Distinguish facts from opinions
A fact is something that can be proved to be true. The month of July has more days than the month of June. This is a fact. It can be proved by looking at a calendar and counting the number of days in each month. An opinion is something that a person believes, thinks, or feels. An opinion cannot be proved true. July is a better month than June for camping. This is an opinion. People may have different opinions about which month is "better" for camping.
The second sentence states a fact. In a beehive, the queen lays eggs while the workers guard the hive. It can be proved by reading a book about bees. The first sentence states an opinion. In a beehive, a worker bee's job is more important than the queen's job. More important shows what a person believes, thinks, or feels. Another person might have a different opinion about which job is more important.
What is the capital of California?
[ "Sacramento", "Salem", "Dover", "Santa Fe" ]
0
closed choice
grade4
social science
geography
State capitals
Identify state capitals of the West
Sacramento is the capital of California.
Select the organism in the same species as the great blue heron.
[ "Strix varia", "Bubo scandiacus", "Ardea herodias" ]
2
This organism is a great blue heron. Its scientific name is Ardea herodias.
closed choice
grade5
natural science
biology
Scientific names
Use scientific names to classify organisms
Scientists use scientific names to identify organisms. Scientific names are made of two words. The first word in an organism's scientific name tells you the organism's genus. A genus is a group of organisms that share many traits. A genus is made up of one or more species. A species is a group of very similar organisms. The second word in an organism's scientific name tells you its species within its genus. Together, the two parts of an organism's scientific name identify its species. For example Ursus maritimus and Ursus americanus are two species of bears. They are part of the same genus, Ursus. But they are different species within the genus. Ursus maritimus has the species name maritimus. Ursus americanus has the species name americanus. Both bears have small round ears and sharp claws. But Ursus maritimus has white fur and Ursus americanus has black fur.
A great blue heron's scientific name is Ardea herodias. Strix varia does not have the same scientific name as a great blue heron. So, Ardea herodias and Strix varia are not in the same species. Ardea herodias has the same scientific name as a great blue heron. So, these organisms are in the same species. Bubo scandiacus does not have the same scientific name as a great blue heron. So, Ardea herodias and Bubo scandiacus are not in the same species.
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Select the one animal that has all of the marsupial traits listed above.
[ "Koalas have fluffy gray fur. Until a baby koala is about seven months old, its mother carries it in a pouch on the front of her body.", "Galapagos giant tortoises hatch from eggs with shells and live on the Galapagos Islands in the Pacific Ocean. They can live to be over 150 years old! Galapagos giant tortoises have scaly, waterproof skin." ]
0
Marsupials are a group of animals with similar traits. The following traits can be used to identify marsupials: They have offspring that lives in the mother's pouch after birth. They have fur or hair. Observe the animals and read the descriptions.
closed choice
grade5
natural science
biology
Classification
Use evidence to classify animals
Scientists sort animals with similar traits into groups. This is called classification. Classification helps scientists learn about how animals live. How do scientists classify animals? First, they make observations about an animal. Scientists observe the animal's traits, including its body parts and behavior. Then, scientists compare the animal's traits to other animals' traits. Scientists classify animals with similar traits into a group.
To decide if an animal is part of a group, look at the traits of the group. Marsupials have the following traits: They have offspring that lives in the mother's pouch after birth. They have fur or hair. Compare each animal's traits to the group's traits. Select the animal with traits similar to the group's traits. A Galapagos giant tortoise has the following traits: It has scaly, waterproof skin. It makes eggs with shells. A Galapagos giant tortoise does not have all of the traits of a marsupial. A Galapagos giant tortoise is a reptile. A koala has the following traits: It has offspring that lives in the mother's pouch after birth. It has fur. A koala has the traits of a marsupial. A koala is a marsupial.
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Is a toy a good or a service?
[ "a good", "a service" ]
0
closed choice
grade2
social science
economics
Economics
Goods and services
Everything you can buy is either a good or a service. A good is something you can touch or hold in your hands. For example, a hammer is a good. A service is a job you pay someone else to do. For example, cooking food in a restaurant is a service.
To decide whether a toy is a good or a service, ask these questions: Is a toy something you can touch? Yes. Is a toy a job you might pay someone else to do? No. So, a toy is a good.
Which solution has a higher concentration of purple particles?
[ "Solution B", "neither; their concentrations are the same", "Solution A" ]
1
The diagram below is a model of two solutions. Each purple ball represents one particle of solute.
closed choice
grade6
natural science
chemistry
Solutions
Compare concentrations of solutions
A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent. The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent. concentration = particles of solute / volume of solvent
In Solution A and Solution B, the 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 and Solution B have the same number of purple particles per milliliter. So, their concentrations are the same.
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Which correctly shows the title of a short story?
[ "\"What the Bell saw and Said\"", "\"What the Bell Saw and Said\"" ]
1
closed choice
grade4
language science
capitalization
Formatting
Capitalizing titles
In a title, capitalize the first word, the last word, and every important word in between. The Wind in the Willows James and the Giant Peach These words are not important in titles: Articles, a, an, the Short prepositions, such as at, by, for, in, of, on, to, up Coordinating conjunctions, such as and, but, or
Capitalize the first word, the last word, and every important word in between. The words the and and are not important, so they should not be capitalized. The correct title is "What the Bell Saw and Said."
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What is the source of the allusion in the sentence below? Troy's Falstaffian nature makes him stand out at a party.
[ "Greek mythology", "Shakespeare" ]
1
closed choice
grade9
language science
figurative-language
Literary devices
Recall the source of an allusion
An allusion is a brief mention of something or someone well known, often from mythology, history, or literature. An allusion lets you reference ideas from an entire story in just a few words. "I'd better get home before I turn into a pumpkin!" Lila remarked. Here, Lila alludes to the fairy tale "Cinderella," in which Cinderella must leave the ball before the coach that brought her transforms into a pumpkin. The allusion shows that Lila must depart immediately.
The source of the allusion Falstaffian is Shakespeare. Sir John Falstaff, a comical character in several of William Shakespeare's plays, is known for his cheerful sociability and sometimes off-color humor. The allusion Falstaffian means characterized by joviality and enjoyment of food and drink.
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Which word does not rhyme?
[ "bait", "mail", "wait" ]
1
closed choice
grade2
language science
phonological-awareness
Rhyming
Which word does not rhyme?
Rhyming words are words that end with the same sound. The words tip and slip rhyme. They both end with the same sound. The words meet and treat also rhyme. They both end with the same sound, even though the sound has two different spellings. The words tip and meet don't rhyme. They end with different sounds.
The words bait and wait rhyme. They both end with the ait sound. The word mail does not rhyme. It ends with a different sound.
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Which figure of speech is used in this text? At twenty-one, Jamal felt overwhelmed with adult responsibilities and wished he could fly off to Neverland.
[ "allusion", "onomatopoeia" ]
0
closed choice
grade7
language science
figurative-language
Literary devices
Classify figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. Alliteration is the repetition of sounds at the beginning of nearby words. What a lucky little lady you are! An allusion is a brief reference to something or someone well known, often from history or literature. "I'd better get home before I turn into a pumpkin!" Lila remarked. An idiom is an expression that cannot be understood literally. Its meaning must be learned. The assignment was a piece of cake. A simile uses like or as to compare two things that are not actually alike. The cat's fur was as dark as the night. A metaphor compares two things that are not actually alike without using like or as. The snow formed a blanket over the town. Onomatopoeia involves using a word that expresses a sound. The scrambled eggs hit the floor with a splat. Personification is giving human characteristics to nonhuman things. The trees danced in the wind. A pun involves using a word or phrase in a humorous way that suggests more than one meaning. A great new broom is sweeping the nation. Verbal irony involves saying one thing but implying something very different. People often use verbal irony when they are being sarcastic. Olivia seems thrilled that her car keeps breaking down. Each breakdown is as enjoyable as a punch to the face.
The text uses an allusion, a brief reference to someone or something well known. Neverland alludes to the story of Peter Pan, a boy who lived in Neverland and never grew up.
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Which of the following contains a vague pronoun reference?
[ "Scott, did you ask the nurses if the flu vaccination is available yet?", "Scott, did you ask them if the flu vaccination is available yet?" ]
1
closed choice
grade7
language science
writing-strategies
Pronouns and antecedents
Identify vague pronoun references
When writing, make sure to avoid vague pronoun references. A vague pronoun reference occurs when a pronoun could refer to more than one possible antecedent. When Lisa and Kim finally landed, she breathed a sigh of relief. The pronoun she could refer to either Lisa or Kim, so the meaning of the sentence is unclear. Vague pronoun references can be corrected in one of two ways: 1. Replace the pronoun with its correct antecedent: When Lisa and Kim finally landed, Lisa breathed a sigh of relief. 2. Rewrite the sentence: Lisa breathed a sigh of relief when she and Kim finally landed. A vague pronoun reference also occurs when they, them, their, theirs, it, or its is used without its antecedent. They say that this nail polish dries in less than five minutes. The pronoun they is used without its antecedent, so the meaning of the sentence is unclear. This problem can be fixed by replacing the pronoun with its missing antecedent. The advertisements say that this nail polish dries in less than five minutes.
The first answer choice contains a vague pronoun reference. The pronoun them is used without its antecedent. The second answer choice shows a possible correction for the vague pronoun reference. Them has been replaced with the nurses. Scott, did you ask the nurses if the flu vaccination is available yet?
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnitude of the magnetic force is smaller in Pair 1.", "The magnitude of the magnetic force is smaller in Pair 2.", "The magnitude of the magnetic force is the same in both pairs." ]
1
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade5
natural science
physics
Magnets
Compare magnitudes of magnetic forces
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other. You can change the magnitude of a magnetic force between two magnets by changing the distance between them. The magnitude of the magnetic force is smaller when there is a greater distance between the magnets.
Distance affects the magnitude of the magnetic force. When there is a greater distance between magnets, the magnitude of the magnetic force between them is smaller. There is a greater distance between the magnets in Pair 2 than in Pair 1. So, the magnitude of the magnetic force is smaller in Pair 2 than in Pair 1.
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Which object has the least thermal energy?
[ "a 4-kilogram brick at a temperature of 281°F", "a 4-kilogram brick at a temperature of 294°F", "a 4-kilogram brick at a temperature of 276°F" ]
2
The objects are identical except for their temperatures.
closed choice
grade4
natural science
physics
Heat and thermal energy
How is temperature related to thermal energy?
All solids, liquids, and gases are made of matter. Matter is made up of tiny particles that are always moving. The energy from the motion of these particles is called thermal energy. Temperature measures how hot or cold matter is. If the particles in matter slow down, the temperature goes down. The matter now has both less thermal energy and a lower temperature.
All three bricks have the same mass but different temperatures. Since the 276°F brick is the coldest, it has the least thermal energy.
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Use the evidence in the text to select the photosynthetic organism.
[ "Javan green magpies get their green color from the food they eat, which includes insects and lizards.", "Bee orchid leaves are green because they contain chlorophyll. Chlorophyll captures energy from sunlight." ]
1
closed choice
grade7
natural science
biology
Photosynthesis
Identify the photosynthetic organism
Organisms that carry out photosynthesis are called photosynthetic organisms. During photosynthesis, these organisms use light energy, carbon dioxide, and water to produce sugars and oxygen. Photosynthetic organisms also often have the following characteristics: They are producers, which are organisms that make their own food inside their cells. Because producers make their own food, they typically do not eat other organisms. Their cells contain chloroplasts, which are cell structures where photosynthesis occurs. Their chloroplasts often contain a green substance called chlorophyll. Chlorophyll captures light energy from the Sun to power photosynthesis. They use the sugars they produce during photosynthesis as food. This food provides energy that helps the organisms live, grow, and reproduce.
This organism is photosynthetic: The text tells you that bee orchids use chlorophyll to capture energy from sunlight. This is evidence that the bee orchid is a photosynthetic organism. This organism is not photosynthetic: The text does not provide evidence that the Javan green magpie is photosynthetic.
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Does this passage describe the weather or the climate? Caleb lives in a city that is often covered by thick stratus clouds.
[ "climate", "weather" ]
0
Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.
closed choice
grade3
natural science
earth-science
Weather and climate
What's the difference between weather and climate?
The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere. Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day. Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures.
Read the text carefully. Caleb lives in a city that is often covered by thick stratus clouds. This passage tells you about the usual clouds where Caleb lives. It does not describe what the weather is like on a particular day. So, this passage describes the climate.
Which of these states is farthest south?
[ "North Carolina", "Rhode Island", "Utah", "Minnesota" ]
0
closed choice
grade3
social science
geography
Geography
Read a map: cardinal directions
Maps have four cardinal directions, or main directions. Those directions are north, south, east, and west. A compass rose is a set of arrows that point to the cardinal directions. A compass rose usually shows only the first letter of each cardinal direction. The north arrow points to the North Pole. On most maps, north is at the top of the map.
To find the answer, look at the compass rose. Look at which way the south arrow is pointing. North Carolina is farthest south.
Which solution has a higher concentration of pink particles?
[ "Solution B", "neither; their concentrations are the same", "Solution A" ]
2
The diagram below is a model of two solutions. Each pink ball represents one particle of solute.
closed choice
grade7
natural science
chemistry
Solutions
Compare concentrations of solutions
A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent. The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent. concentration = particles of solute / volume of solvent
In Solution A and Solution B, the 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 has more pink particles per milliliter. So, Solution A has a higher concentration of pink particles.
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Select the vertebrate.
[ "green iguana", "julia butterfly", "black orb weaver spider", "bull ant" ]
0
Hint: Mammals, birds, fish, reptiles, and amphibians are vertebrates.
closed choice
grade5
natural science
biology
Classification
Identify vertebrates and invertebrates
Vertebrates and invertebrates are both groups of animals. A vertebrate has a backbone. The backbone is made of many bones in an animal's back. A vertebrate's backbone helps connect the different parts of its body. In the drawings below, each vertebrate's backbone is colored orange. An invertebrate does not have a backbone. In fact, invertebrates do not have any bones! Some invertebrates have an outer cover on their body called an exoskeleton. Other invertebrates have a soft body.
A bull ant is an insect. Like other insects, a bull ant is an invertebrate. It does not have a backbone. It has an exoskeleton. Like other spiders, a black orb weaver spider is an invertebrate. It does not have a backbone. It has an exoskeleton. A julia butterfly is an insect. Like other insects, a julia butterfly is an invertebrate. It does not have a backbone. It has an exoskeleton. A green iguana is a reptile. Like other reptiles, a green iguana is a vertebrate. It has a backbone.
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Which object has more thermal energy?
[ "a 9-kilogram block of iron at a temperature of 175°C", "a 9-kilogram block of iron at a temperature of 165°C" ]
0
The objects are identical except for their temperatures.
closed choice
grade3
natural science
physics
Heat and thermal energy
How is temperature related to thermal energy?
All solids, liquids, and gases are made of matter. Matter is made up of tiny particles that are always moving. The energy from the motion of these particles is called thermal energy. Temperature measures how hot or cold matter is. If the particles in matter move faster, the temperature goes up. The matter now has both more thermal energy and a higher temperature.
The two blocks of iron have the same mass but different temperatures. Since the 175°C block is hotter than the 165°C block, it has more thermal energy.
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What does the verbal irony in this text suggest? "Sleeping through the rooster's crowing was no problem," Brennan joked with a yawn.
[ "Brennan finds roosters amusing.", "Brennan slept poorly." ]
1
closed choice
grade7
language science
figurative-language
Literary devices
Interpret figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. Verbal irony involves saying one thing but implying something very different. People often use verbal irony when they are being sarcastic. Olivia seems thrilled that her car keeps breaking down. Each breakdown is as enjoyable as a punch to the face.
The text uses verbal irony, which involves saying one thing but implying something very different. Sleeping through the rooster's crowing was no problem ironically suggests that Brennan slept poorly. Brennan was tired, so the rooster's crowing was clearly a problem.
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Would you find the word belief on a dictionary page with the following guide words? bind - bug
[ "yes", "no" ]
1
yes or no
grade7
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since belief is not between the guide words bind - bug, it would not be found on that page.
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What do these two changes have in common? a puddle freezing into ice on a cold night shaking up salad dressing
[ "Both are caused by heating.", "Both are chemical changes.", "Both are caused by cooling.", "Both are only physical changes." ]
3
closed choice
grade8
natural science
chemistry
Chemical reactions
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form different molecules. The types of molecules in matter before and after a chemical change are always different. Some chemical changes are caused by heating or cooling. For example, burning a piece of paper is a chemical change caused by heating. As paper burns, paper molecules react with oxygen molecules in the air. This reaction breaks the chemical bonds in the molecules. The atoms then link together in a different way to form different molecules. For example, carbon dioxide molecules are formed when paper burns. In a physical change, chemical bonds do not break. The types of molecules in matter before and after a physical change are always the same. A change of state is a type of physical change. Changes of state can be caused by heating or cooling. For example, water vaporizing is a physical change that can be caused by heating. Liquid water and water vapor are made of the same type of matter: water. The law of conservation of mass says that all physical and chemical changes conserve mass. Conserve means to keep the same. So, the total mass before a physical or chemical change is equal to the total mass after the change.
Step 1: Think about each change. A puddle freezing into ice on a cold night is a change of state. So, it is a physical change. Liquid water freezes and becomes solid, but it is still made of water. A different type of matter is not formed. Shaking up salad dressing is a physical change. The different parts mix together, but they are still made of the same type of matter. Step 2: Look at each answer choice. Both are only physical changes. Both changes are physical changes. No new matter is created. Both are chemical changes. Both changes are physical changes. They are not chemical changes. Both are caused by heating. Neither change is caused by heating. Both are caused by cooling. A puddle freezing is caused by cooling. But shaking up salad dressing is not.
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Complete the sentence so that it uses personification. The wind () dispersed the leaves that Zack had spent so long raking.
[ "completely", "carelessly" ]
1
closed choice
grade9
language science
writing-strategies
Creative techniques
Use personification
Personification is giving human characteristics to nonhuman things. It is a figure of speech that can be used to make writing more interesting or to emphasize a point. The trees danced in the wind. The word danced describes the trees as if they were people. Unlike people, however, trees can't actually dance. Instead, the personification suggests that the trees are moving.
Complete the sentence with the word carelessly. It describes the wind as if it were a person who didn't care.
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Would you find the word period on a dictionary page with the following guide words? pity - practice
[ "no", "yes" ]
0
yes or no
grade8
language science
reference-skills
Reference skills
Use guide words
Guide words appear on each page of a dictionary. They tell you the first word and last word on the page. The other words on the page come between the guide words in alphabetical order. To put words in alphabetical order, put them in order by their first letters. If the first letters are the same, look at the second letters. If the second letters are the same, look at the third letters, and so on. If one word is shorter, and there are no more letters to compare, then the shorter word comes first in alphabetical order. For example, be comes before bed.
Put the words in alphabetical order. Since period is not between the guide words pity - practice, it would not be found on that page.
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Which figure of speech is used in this text? Jonathan's room is as tidy as an overgrown garden.
[ "pun", "verbal irony" ]
1
closed choice
grade7
language science
figurative-language
Literary devices
Classify figures of speech
Figures of speech are words or phrases that use language in a nonliteral or unusual way. They can make writing more expressive. Alliteration is the repetition of sounds at the beginning of nearby words. What a lucky little lady you are! An allusion is a brief reference to something or someone well known, often from history or literature. "I'd better get home before I turn into a pumpkin!" Lila remarked. An idiom is an expression that cannot be understood literally. Its meaning must be learned. The assignment was a piece of cake. A simile uses like or as to compare two things that are not actually alike. The cat's fur was as dark as the night. A metaphor compares two things that are not actually alike without using like or as. The snow formed a blanket over the town. Onomatopoeia involves using a word that expresses a sound. The scrambled eggs hit the floor with a splat. Personification is giving human characteristics to nonhuman things. The trees danced in the wind. A pun involves using a word or phrase in a humorous way that suggests more than one meaning. A great new broom is sweeping the nation. Verbal irony involves saying one thing but implying something very different. People often use verbal irony when they are being sarcastic. Olivia seems thrilled that her car keeps breaking down. Each breakdown is as enjoyable as a punch to the face.
The text uses verbal irony, which involves saying one thing but implying something very different. As tidy as an overgrown garden shows verbal irony because an overgrown garden is not tidy.
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Select the animal that has a backbone.
[ "kangaroo", "comet moth" ]
0
Hint: Mammals, birds, fish, reptiles, and amphibians all have backbones.
closed choice
grade2
natural science
biology
Classification
Identify animals with and without backbones
Some animals have a backbone. The backbone is made of many bones in an animal's back. An animal's backbone helps connect the different parts of its body. In the drawings below, each animal's backbone is colored orange. Other animals do not have a backbone. In fact, these animals don't have any bones! Some animals without backbones have a hard outer cover. Other animals have a soft body.
A comet moth is an insect. Like other insects, a comet moth does not have a backbone. It has a hard outer cover. A kangaroo is a mammal. Like other mammals, a kangaroo has a backbone.
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Complete the sentence. Water evaporating from a lake is a ().
[ "chemical change", "physical change" ]
1
closed choice
grade3
natural science
chemistry
Physical and chemical change
Identify physical and chemical changes
Chemical changes and physical changes are two common ways matter can change. In a chemical change, the type of matter changes. The types of matter before and after a chemical change are always different. Burning a piece of paper is a chemical change. When paper gets hot enough, it reacts with oxygen in the air and burns. The paper and oxygen change into ash and smoke. In a physical change, the type of matter stays the same. The types of matter before and after a physical change are always the same. Cutting a piece of paper is a physical change. The cut pieces are still made of paper. A change of state is a type of physical change. For example, ice melting is a physical change. Ice and liquid water are made of the same type of matter: water.
Water evaporating from a lake is a change of state. So, it is a physical change. The liquid changes into a gas, but a different type of matter is not formed.
Select the chemical formula for this molecule.
[ "SiH4", "SiHe", "SiHe4", "Si2H4" ]
0
closed choice
grade5
natural science
chemistry
Atoms and molecules
Match chemical formulas to ball-and-stick models
Every substance around you is made up of atoms. Atoms can link together to form molecules. The links between atoms in a molecule are called chemical bonds. Different molecules are made up of different chemical elements, or types of atoms, bonded together. Scientists use both ball-and-stick models and chemical formulas to represent molecules. A ball-and-stick model of a molecule is shown below. The balls represent atoms. The sticks represent the chemical bonds between the atoms. Notice how each ball is labeled with a symbol made of one or more letters. The symbol is an abbreviation for a chemical element. The ball represents one atom of that element. Every chemical element is represented by its own symbol. For some elements, that symbol is one capital letter. For other elements, it is one capital letter followed by one lowercase letter. For example, the symbol for the element boron is B and the symbol for the element chlorine is Cl. The molecule shown above has one boron atom and three chlorine atoms. A chemical bond links each chlorine atom to the boron atom. The chemical formula for a molecule contains the symbol for each chemical element in the molecule. Many chemical formulas use subscripts. A subscript is text that is smaller and placed lower than the normal line of text. In chemical formulas, the subscripts are numbers. The subscript is always written after the symbol for an element. The subscript tells you how many atoms that symbol represents. If the symbol represents just one atom, then no subscript is included. The symbols in the chemical formula for a molecule match the symbols in the ball-and-stick model for that molecule. The ball-and-stick model shown before and the chemical formula shown above represent the same substance.
Si is the symbol for silicon. H is the symbol for hydrogen. This ball-and-stick model shows a molecule with one silicon atom and four hydrogen atoms. The chemical formula will contain the symbols Si and H. There is one silicon atom, so Si will not have a subscript. There are four hydrogen atoms, so H will have a subscript of 4. The correct formula is SiH4. The diagram below shows how each part of the chemical formula matches with each part of the model above.
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Select the one true statement.
[ "An animal cell has neither a cell wall nor chloroplasts.", "Lysosomes are the sites where ribosomes build proteins in animal cells.", "Mitochondria are inside the nucleus of a plant cell." ]
0
closed choice
grade7
natural science
biology
Cells
Compare cells and cell parts
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What information supports the conclusion that Tony inherited this trait?
[ "Tony's parents have blond hair. They passed down this trait to Tony.", "Tony's mother cuts his hair every month." ]
0
Read the description of a trait. Tony has blond hair.
closed choice
grade5
natural science
biology
Traits and heredity
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment.
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Complete the sentence. Making whipped cream is a ().
[ "chemical change", "physical change" ]
1
closed choice
grade5
natural science
chemistry
Physical and chemical change
Compare physical and chemical changes
Matter is made of very small particles called atoms. Atoms can be linked together by chemical bonds. When two or more atoms link together, they form a molecule. In a chemical change, the chemical bonds in the molecules break. The atoms then link together to form new molecules. The types of molecules in matter before and after a chemical change are always different. Burning a piece of paper is a chemical change. As paper burns, paper molecules react with oxygen molecules in the air. This reaction breaks the chemical bonds in the molecules. The atoms then relink and form different molecules. For example, carbon dioxide molecules are created when paper burns. In a physical change, chemical bonds do not break. The types of molecules in matter before and after a physical change are always the same. A change of state is a type of physical change. For example, water vaporizing is a physical change. Liquid water and water vapor are made of the same type of matter: water.
Making whipped cream is a physical change. Whipped cream is a mixture of cream and air. But making a mixture does not form a different type of matter. As cream is whipped, its molecules begin to stick together. But the bonds between the atoms in the molecules do not change. Air gets trapped between the molecules in the cream. This makes the cream fluffy.
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Suppose Natalie decides to make potato soup. Which result would be a cost?
[ "Natalie will save some time. The beef barley soup would have taken longer to make than the potato soup.", "Natalie will give up the chance to eat the beef barley soup, which would have been tastier than the potato soup." ]
1
Natalie is deciding whether to make beef barley soup or potato soup for dinner. She wants dinner to be as tasty as possible. But she is also hungry and wants to eat soon.
closed choice
grade5
social science
economics
Basic economic principles
Costs and benefits
Before you decide to do something, it is often helpful to list costs and benefits. Costs are what you give up or spend when you decide to do something. Costs involve giving up things that you want or need. Benefits are what you gain or save when you decide to do something. Benefits involve gaining something that you want or need.
This result is a cost. It involves giving up or spending something that Natalie wants or needs: Natalie will give up the chance to eat the beef barley soup, which would have been tastier than the potato soup.
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What information supports the conclusion that Ariana inherited this trait?
[ "Ariana's father has brown eyes. He passed this trait down to Ariana.", "Ariana's hair is the same color as her brown eyes." ]
0
Read the description of a trait. Ariana has brown eyes.
closed choice
grade5
natural science
biology
Traits and heredity
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment.
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Which is a complex sentence?
[ "Kenny picked raspberries in the field until his fingertips were stained red.", "In June, Sue and Mitchell will graduate with honors from Clarksville High School." ]
0
closed choice
grade6
language science
grammar
Sentences, fragments, and run-ons
Is the sentence simple, compound, or complex?
A clause is a group of words that contains both a subject and a predicate. An independent clause is a complete thought. It can stand alone as a sentence. A dependent clause is not a complete thought. It cannot stand alone as a sentence. the oranges on our tree are ripe The clause can stand alone. It is independent. after we pick up Kevin from work The clause cannot stand alone. It is dependent. A simple sentence is made up of a single independent clause. Ben and I spent all day relaxing by the pool. Some simple sentences have introductory phrases, but the introductory phrase is part of the predicate. In the winter, Ben usually wears his heavy coat. Ben usually wears his heavy coat in the winter. A compound sentence is made up of two independent clauses joined by a coordinating conjunction such as and, but, or, or so. We saw a flash of lightning, and seconds later we heard the rumble of thunder. A complex sentence is made up of an independent clause and a dependent clause. The dependent clause usually begins with a subordinating conjunction such as after, although, as, because, before, if, since, unless, until, when, or while. If she ever gets the chance, Terri would love to visit the Egyptian pyramids.
The first sentence is the complex sentence. It is made up of an independent clause and a dependent clause. The dependent clause begins with the subordinating conjunction until. Kenny picked raspberries in the field until his fingertips were stained red.
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Which of the following contains a vague pronoun reference?
[ "Alice and her husband met Jill for lunch at a small café around the block from her office.", "Alice and her husband met Jill for lunch at a small café around the block from Jill's office." ]
0
closed choice
grade11
language science
writing-strategies
Pronouns
Identify vague pronoun references
When writing, make sure to avoid vague pronoun references. A vague pronoun reference occurs when a pronoun could refer to more than one possible antecedent. When Lisa and Kim finally landed, she breathed a sigh of relief. The pronoun she could refer to either Lisa or Kim, so the meaning of the sentence is unclear. Vague pronoun references can be corrected in one of two ways: 1. Replace the pronoun with its correct antecedent: When Lisa and Kim finally landed, Lisa breathed a sigh of relief. 2. Rewrite the sentence: Lisa breathed a sigh of relief when she and Kim finally landed. A vague pronoun reference also occurs when they, them, their, theirs, it, or its is used without its antecedent. They say that this nail polish dries in less than five minutes. The pronoun they is used without its antecedent, so the meaning of the sentence is unclear. This problem can be fixed by replacing the pronoun with its missing antecedent. The advertisements say that this nail polish dries in less than five minutes.
The second answer choice contains a vague pronoun reference. The pronoun her could refer to Alice or Jill. The first answer choice shows a possible correction for the vague pronoun reference. Her has been replaced with Jill's. Alice and her husband met Jill for lunch at a small café around the block from Jill's office.
Which trait did Meiolania have? Select the trait you can observe on the fossil.
[ "front and back legs", "long, thin antennae" ]
0
This picture shows a fossil of an ancient animal called Meiolania. An adult Meiolania was about eight feet long.
closed choice
grade6
natural science
earth-science
Fossils
Compare fossils to modern organisms
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.
Select the bird below.
[ "robin", "American bullfrog" ]
0
Birds have feathers, two wings, and a beak. A pelican is an example of a bird.
closed choice
grade2
natural science
biology
Classification
Identify mammals, birds, fish, reptiles, and amphibians
Birds, mammals, fish, reptiles, and amphibians are groups of animals. The animals in each group have traits in common. Scientists sort animals into groups based on traits they have in common. This process is called classification.
An American bullfrog is an amphibian. It has moist skin and begins its life in water. A robin is a bird. It has feathers, two wings, and a beak.
Does this passage describe the weather or the climate?
[ "weather", "climate" ]
1
Figure: Gobi Desert. A high pressure system can push clouds out of an area. The Gobi Desert has high pressure for 250 days per year on average. Hint: Weather is what the atmosphere is like at a certain place and time. Climate is the pattern of weather in a certain place.
closed choice
grade6
natural science
earth-science
Weather and climate
Weather and climate around the world
The atmosphere is the layer of air that surrounds Earth. Both weather and climate tell you about the atmosphere. Weather is what the atmosphere is like at a certain place and time. Weather can change quickly. For example, the temperature outside your house might get higher throughout the day. Climate is the pattern of weather in a certain place. For example, summer temperatures in New York are usually higher than winter temperatures.
Read the passage carefully. A high pressure system can push clouds out of an area. The Gobi Desert has high pressure for 250 days per year on average. The underlined part of the passage tells you about the usual pattern of barometric pressure in the Gobi Desert. This passage does not describe what the weather is like on a particular day. So, this passage describes the climate.
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Using only these supplies, which question can Danny investigate with an experiment?
[ "Do toy cars go faster down the ramp made of wood or the ramp made of cardboard?", "Does a big toy car go down the wooden ramp faster than a small toy car?", "Do toy cars with plastic wheels go faster down the cardboard ramp than toy cars with metal wheels?" ]
0
Danny and his sister are building ramps to race their toy cars down. Danny notices that the cars go down some of the ramps faster than others. He wonders what factors affect the cars' speed. So, he decides to design an experiment. He has the following supplies available: two identical toy cars a wooden ramp three feet long and two feet tall a cardboard ramp three feet long and two feet tall
closed choice
grade7
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
Which solution has a higher concentration of pink particles?
[ "Solution B", "Solution A", "neither; their concentrations are the same" ]
1
The diagram below is a model of two solutions. Each pink ball represents one particle of solute.
closed choice
grade6
natural science
chemistry
Solutions
Compare concentrations of solutions
A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent. The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent. concentration = particles of solute / volume of solvent
In Solution A and Solution B, the 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 has more pink particles per milliliter. So, Solution A has a higher concentration of pink particles.
Based on the arrows, which of the following organisms is an omnivore?
[ "barren-ground caribou", "grizzly bear" ]
1
Below is a food web from a tundra ecosystem in Nunavut, a territory in Northern Canada. A food web models how the matter eaten by organisms moves through an ecosystem. The arrows in a food web represent how matter moves between organisms in an ecosystem.
closed choice
grade4
natural science
biology
Ecosystems
Interpret food webs
A food web is a model. A food web shows where organisms in an ecosystem get their food. Models can make things in nature easier to understand because models can represent complex things in a simpler way. If a food web showed every organism in an ecosystem, the food web would be hard to understand. So, each food web shows how some organisms in an ecosystem can get their food. Arrows show how matter moves. A food web has arrows that point from one organism to another. Each arrow shows the direction that matter moves when one organism eats another organism. An arrow starts from the organism that is eaten. The arrow points to the organism that is doing the eating. An organism in a food web can have more than one arrow pointing from it. This shows that the organism is eaten by more than one other organism in the food web. An organism in a food web can also have more than one arrow pointing to it. This shows that the organism eats more than one other organism in the food web.
Omnivores are consumers that eat both producers and other consumers. So, an omnivore has arrows pointing to it from at least one producer and at least one consumer. The grizzly bear has an arrow pointing to it from the bilberry, which is a producer. The grizzly bear also has an arrow pointing to it from the barren-ground caribou, which is a consumer. The grizzly bear eats a producer and a consumer, so it is an omnivore. The barren-ground caribou has only one arrow pointing to it. This arrow starts from the lichen, which is a producer. So, the barren-ground caribou is a consumer but not an omnivore.
Is the following statement about our solar system true or false? Jupiter's volume is more than ten times as large as Saturn's volume.
[ "true", "false" ]
1
Use the data to answer the question below.
true-or false
grade8
natural science
earth-science
Astronomy
Analyze data to compare properties of planets
A planet's volume tells you the size of the planet. The primary composition of a planet is what the planet is made mainly of. In our solar system, planets are made mainly of rock, gas, or ice. The volume of a planet is a very large quantity. Large quantities such as this are often written in scientific notation. For example, the volume of Jupiter is 1,430,000,000,000,000 km^3. In scientific notation, Jupiter's volume is written as 1.43 x 10^15 km^3. To compare two numbers written in scientific notation, first compare their exponents. The bigger the exponent is, the bigger the number is. For example: 1.43 x 10^15 is larger than 1.43 x 10^12 If their exponents are equal, compare the first numbers. For example: 1.43 x 10^15 is larger than 1.25 x 10^15 To multiply a number written in scientific notation by a power of 10, write the multiple of 10 as 10 raised to an exponent. Then, add the exponents. For example: 1.43 x 10^15 · 1000 = 1.43 x 10^15 · 10^3 = 1.43 x 10^(15 + 3) = 1.43 x 10^18
To determine if this statement is true, calculate the value of ten times the volume of Saturn. Then compare the result to the volume of Jupiter. The volume of Jupiter is 1.43 x 10^15 km^3, which is less than 8.27 x 10^15 km^3. So, Jupiter's volume is less than ten times as large as Saturn's volume.
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Using only these supplies, which question can Kamal investigate with an experiment?
[ "Do rubber balloons stick to a wooden door or a metal door longer after being rubbed on his hair?", "Do rubber balloons or foil balloons stick to the wooden door longer after being rubbed on his hair?", "Do rubber balloons stick to a cotton blanket or a wooden door longer after being rubbed on his hair?" ]
2
Kamal went to a magic show. The magician rubbed a balloon on her hair and then held the balloon against a wall. When the magician released the balloon, Kamal was amazed to see that it stuck to the wall! He wonders what factors affect how well balloons stick to different surfaces. So, he decides to design an experiment. He has the following supplies available: the hair on his own head a cotton blanket a wooden door five rubber balloons
closed choice
grade8
natural science
science-and-engineering-practices
Designing experiments
Identify questions that can be investigated with a set of materials
Experiments can be designed to answer specific questions. When designing an experiment, you must identify the supplies that are necessary to answer your question. In order to do this, you need to figure out what will be tested and what will be measured during the experiment. Imagine that you are wondering if plants grow to different heights when planted in different types of soil. How might you decide what supplies are necessary to conduct this experiment? First, you need to identify the part of the experiment that will be tested, which is the independent variable. This is usually the part of the experiment that is different or changed. In this case, you would like to know how plants grow in different types of soil. So, you must have different types of soil available. Next, you need to identify the part of the experiment that will be measured or observed, which is the dependent variable. In this experiment, you would like to know if some plants grow taller than others. So, you must be able to compare the plants' heights. To do this, you can observe which plants are taller by looking at them, or you can measure their exact heights with a meterstick. So, if you have different types of soil and can observe or measure the heights of your plants, then you have the supplies you need to investigate your question with an experiment!
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What information supports the conclusion that Russell acquired this trait?
[ "Russell learned biology by doing experiments.", "Russell is most interested in plant biology." ]
0
Read the description of a trait. Russell knows a lot about biology.
closed choice
grade3
natural science
biology
Heredity
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment.
What is the capital of Massachusetts?
[ "Plymouth", "Montgomery", "Boston", "Hartford" ]
2
closed choice
grade4
social science
geography
State capitals
Identify state capitals of the Northeast
Boston is the capital of Massachusetts.
What type of rock is peridotite?
[ "sedimentary", "metamorphic", "igneous" ]
2
This is a piece of peridotite. Peridotite is made mostly of the mineral olivine. Olivine gives the rock its greenish color. Peridotite forms through the cooling of melted rock. It is usually found deep below the earth's surface. Scientists think that a large part of the earth's mantle is made of peridotite.
closed choice
grade7
natural science
earth-science
Rocks and minerals
Classify rocks as igneous, sedimentary, or metamorphic
Igneous rock is formed when melted rock cools and hardens into solid rock. This type of change can occur at Earth's surface or below it. Sedimentary rock is formed when layers of sediment are pressed together, or compacted, to make rock. This type of change occurs below Earth's surface. Metamorphic rock is formed when a rock is changed by very high temperature and pressure. This type of change often occurs deep below Earth's surface. Over time, the old rock becomes a new rock with different properties.
Peridotite is an igneous rock. Like other igneous rocks, it forms when melted rock cools and hardens. Melted rock below the earth's surface is called magma. Peridotite forms from magma that is very rich in iron and magnesium. As the magma cools, minerals such as olivine begin to form. When the magma becomes solid, it turns into peridotite.
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What is the volume of a soda bottle cap?
[ "10 liters", "10 milliliters" ]
1
Select the better estimate.
closed choice
grade5
natural science
units-and-measurement
Units and measurement
Choose metric units of volume
Measurements are written with both a number and a unit. The unit comes after the number. The unit shows what the number means. Volume is a measurement of how much space something takes up. There are many different units of volume. When you are using metric units, volume may be written in units of milliliters or liters. There are 1,000 milliliters in 1 liter. So, 1 milliliter is much less than 1 liter. A raindrop has a volume of about 20 milliliters, while a large soda bottle has a volume of 2 liters. The flask shown here measures volumes up to 500 milliliters.
The better estimate for the volume of a soda bottle cap is 10 milliliters. 10 liters is too much.
Which solution has a higher concentration of green particles?
[ "Solution B", "neither; their concentrations are the same", "Solution A" ]
0
The diagram below is a model of two solutions. Each green ball represents one particle of solute.
closed choice
grade8
natural science
chemistry
Solutions
Compare concentrations of solutions
A solution is made up of two or more substances that are completely mixed. In a solution, solute particles are mixed into a solvent. The solute cannot be separated from the solvent by a filter. For example, if you stir a spoonful of salt into a cup of water, the salt will mix into the water to make a saltwater solution. In this case, the salt is the solute. The water is the solvent. The concentration of a solute in a solution is a measure of the ratio of solute to solvent. Concentration can be described in terms of particles of solute per volume of solvent. concentration = particles of solute / volume of solvent
In Solution A and Solution B, the green particles represent the solute. To figure out which solution has a higher concentration of green particles, look at both the number of green particles and the volume of the solvent in each container. Use the concentration formula to find the number of green particles per milliliter. Solution B has more green particles per milliliter. So, Solution B has a higher concentration of green particles.
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Which sentence states a fact?
[ "Bananas taste great with melted chocolate.", "Bananas turn yellow as they become ripe." ]
1
closed choice
grade3
language science
writing-strategies
Opinion writing
Distinguish facts from opinions
A fact is something that can be proved to be true. The month of July has more days than the month of June. This is a fact. It can be proved by looking at a calendar and counting the number of days in each month. An opinion is something that a person believes, thinks, or feels. An opinion cannot be proved true. July is a better month than June for camping. This is an opinion. People may have different opinions about which month is "better" for camping.
The first sentence states a fact. Bananas turn yellow as they become ripe. It can be proved by observing bananas as they ripen. The second sentence states an opinion. Bananas taste great with melted chocolate. Great shows what a person believes, thinks, or feels. Another person might have a different opinion about how bananas with melted chocolate taste.
Which ocean is highlighted?
[ "the Southern Ocean", "the Atlantic Ocean", "the Arctic Ocean", "the Indian Ocean" ]
3
closed choice
grade7
social science
geography
Physical Geography
Oceans and continents
Oceans are huge bodies of salt water. The world has five oceans. All of the oceans are connected, making one world ocean.
This is the Indian Ocean.
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Select the living thing.
[ "cat", "house" ]
0
closed choice
grade3
natural science
biology
Classification
Identify living and nonliving things
All living things need food and water. Water helps living things break down food and remove waste. Food gives living things energy. Living things use this energy to grow and change. All living things grow and change during their lives. All living things sense changes in the world around them. Living things might sense changes by seeing, smelling, hearing, or feeling. Living things can respond to the changes they sense.
A cat is a living thing. Cats grow and respond to the world around them. They need food and water. A house is not a living thing. Houses do not have all of the traits of living things. They do not grow or respond to the world around them. They do not need food or water.
Think about the magnetic force between the magnets in each pair. Which of the following statements is true?
[ "The magnitude of the magnetic force is smaller in Pair 2.", "The magnitude of the magnetic force is the same in both pairs.", "The magnitude of the magnetic force is smaller in Pair 1." ]
1
The images below show two pairs of magnets. The magnets in different pairs do not affect each other. All the magnets shown are made of the same material.
closed choice
grade8
natural science
physics
Velocity, acceleration, and forces
Compare magnitudes of magnetic forces
Magnets can pull or push on each other without touching. When magnets attract, they pull together. When magnets repel, they push apart. These pulls and pushes between magnets are called magnetic forces. The strength of a force is called its magnitude. The greater the magnitude of the magnetic force between two magnets, the more strongly the magnets attract or repel each other.
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.
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Which correctly shows the title of a poem?
[ "\"About the Teeth of Sharks\"", "\"about the teeth of Sharks\"" ]
0
closed choice
grade4
language science
capitalization
Formatting
Capitalizing titles
In a title, capitalize the first word, the last word, and every important word in between. The Wind in the Willows James and the Giant Peach These words are not important in titles: Articles, a, an, the Short prepositions, such as at, by, for, in, of, on, to, up Coordinating conjunctions, such as and, but, or
Capitalize the first word, the last word, and every important word in between. The words the and of are not important, so they should not be capitalized. The correct title is "About the Teeth of Sharks."
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Based on this information, what is this pea plant's phenotype for the pod shape trait?
[ "constricted pods", "dd" ]
0
This passage describes the pod shape trait in pea plants: In a group of pea plants, some individuals have inflated pods and others have constricted pods. In this group, the gene for the pod shape trait has two alleles. The allele D is for inflated pods, and the allele d is for constricted pods. A certain pea plant from this group has constricted pods. This plant has two alleles for constricted pods.
closed choice
grade8
natural science
biology
Genes to traits
Genetics vocabulary: genotype and phenotype
All organisms have pieces of hereditary material called genes, which are passed from parents to offspring. Genes contain instructions for building the parts of an organism. An organism's genes affect its observable traits, including its appearance, its behavior, and which diseases it may have. Genes may have different alleles, or forms, that can cause different versions of a trait. For example, flower color is a trait in pea plants. The gene for this trait has two possible alleles. Each allele is represented by an uppercase or lowercase letter. The allele F is for purple flowers, and the allele f is for white flowers. Each pea plant has two alleles for the flower color gene—one allele inherited from each parent. An organism's genotype for a gene is its combination of alleles for that gene. So, a pea plant may have a genotype of FF, Ff, or ff for the flower color gene. An organism's phenotype for a trait is its observable version of that trait, which depends on the organism's combination of alleles. A pea plant may have a phenotype of purple flowers or white flowers for the flower color trait.
An organism's phenotype for a trait is its observable version of that trait. The pea plant's observable version of the pod shape trait is constricted pods. So, the plant's phenotype for the pod shape trait is constricted pods.
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What information supports the conclusion that Fred acquired this trait?
[ "Fred learned how to build a fire at summer camp.", "Fred can cook food over a fire." ]
0
Read the description of a trait. Fred knows how to build a fire.
closed choice
grade3
natural science
biology
Heredity
Inherited and acquired traits: use evidence to support a statement
Organisms, including people, have both inherited and acquired traits. Inherited and acquired traits are gained in different ways. Inherited traits are passed down through families. Children gain these traits from their parents. Inherited traits do not need to be learned. Acquired traits are gained during a person's life. Some acquired traits, such as riding a bicycle, are gained by learning. Other acquired traits, such as scars, are caused by the environment.
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Is a toothbrush a good or a service?
[ "a service", "a good" ]
1
closed choice
grade2
social science
economics
Economics
Goods and services
Everything you can buy is either a good or a service. A good is something you can touch or hold in your hands. For example, a hammer is a good. A service is a job you pay someone else to do. For example, cooking food in a restaurant is a service.
To decide whether a toothbrush is a good or a service, ask these questions: Is a toothbrush something you can touch? Yes. Is a toothbrush a job you might pay someone else to do? No. So, a toothbrush is a good.
Which of the following could Ken's test show?
[ "whether an inexpensive filter would become clogged more often", "the amount of bacteria in the water before it was filtered", "whether the filter was clogged" ]
2
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. Ken was . At the plant, an expensive filter was used to remove disease-causing bacteria from the water. But over time, the filter would become clogged with bacteria. If the filter became clogged, the water would not move through quickly enough. Ken had to decide when the filter was too clogged and needed to be replaced. So, during his inspection, Ken checked the filter by measuring how quickly water moved through it. Figure: an engineer at a water treatment plant.
closed choice
grade7
natural science
science-and-engineering-practices
Engineering practices
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.
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Complete the sentence. Cesar Chavez came from () family.
[ "an African American", "a Mexican American", "a Chinese American", "a French American" ]
1
closed choice
grade3
social science
us-history
Historical figures
Cesar Chavez
Cesar Chavez came from a Mexican American family: His father's parents were from Mexico. They moved to the United States in 1880. Cesar Chavez's father was born in Arizona. Cesar Chavez's mother was born in Mexico. She and her family moved to Arizona when she was six months old. Cesar Chavez was born in the United States in 1927. During Cesar Chavez's life, he and many other Mexican American people were treated unfairly because of their heritage. Cesar Chavez worked to fight this unequal treatment.
Which bird's beak is also adapted to filter through mud?
[ "spotted munia", "Canada goose" ]
1
Ringed teals eat invertebrates and plants that live near water. The shape of the 's beak is adapted to filter through mud for food. The gathers muddy water in its beak and then pushes it out through gaps along the sides. Bits of food, such as plant roots, are left behind inside the teal's beak. Figure: ringed teal.
closed choice
grade5
natural science
biology
Adaptations
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.
Look at the picture of the ringed teal. The ringed teal has a wide, flat beak. Its beak is adapted to filter through mud. The ringed teal gathers muddy water in its beak. Then, it pushes the water out through gaps along the sides of the beak. Bits of food, such as plant roots, are left behind inside the teal's beak. Now look at each bird. Figure out which bird has a similar adaptation. The Canada goose has a wide, flat beak. Its beak is adapted to filter through mud. The spotted munia has a short, thick beak. Its beak is not adapted to filter through mud. The spotted munia uses its beak to eat small, hard seeds.