You are given a paragraph, with numbered sentences, and a question. Write the numbers of the sentences needed to answer the given question. Separate multiple sentence numbers with a comma (", "). E.g. "1, 2" would be the correct response if Sent 1 and Sent 2 are needed to answer the given question (do not include sentences that contain no information that is necessary to answer the question). Sort the sentence numbers in an increasing order (i.e., '1, 2', instead of '2, 1'). Your answer should not contain anything than the sentence numbers separated by a comma (e.g. '1, 2, 3, 4'). The given question requires more than one sentence to answer. So, your answer must contain at least one comma (", ").

Q: Paragraph- Sent 1: Energy is the ability to do work.
Sent 2: Another way to say this is, the ability to cause change.
Sent 3: Work is done when a force is used to move something.
Sent 4: When work is done, energy is transferred.
Sent 5: This transfer occurs between one object and another.
Sent 6: For example, a batter swings a bat and transfers energy.
Sent 7: She transfers her energy to the bat.
Sent 8: The moving bat, in turn, transfers energy to the ball.
Sent 9: Energy is measured in the Joule (J).
Sent 10: Energy exists in many forms.
Sent 11: One form of energy is called mechanical.
Sent 12: Mechanical energy is the energy of motion.
Sent 13: This type of energy can also include things that are not yet in motion.
Sent 14: In these cases, they have only a potential to be in motion.
Sent 15: In most cases, this ability comes from a position.
Sent 16: A rock sitting on top of a cliff has potential energy.
Sent 17: It is more than just the ability.
Sent 18: A rock sitting on the ground could move if someone picked it up.
Question: What kind of energy is mechanical energy?.

A: 11, 12.
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Q: Paragraph- Sent 1: Sometimes traits can vary from parent to offspring.
Sent 2: These changes are due to mutations.
Sent 3: Mutations are a random change.
Sent 4: Mutations are natural.
Sent 5: Some mutations are harmful.
Sent 6: In this case, the organism may not live to reproduce.
Sent 7: The trait will not be passed onto offspring.
Sent 8: Others variations in traits have no effect on survival.
Sent 9: Can some mutations be good for a living thing?
Sent 10: Other mutations can have great benefits.
Sent 11: Imagine being the first moth that can blend into its background.
Sent 12: It would have a better chance of survival.
Sent 13: A living thing that survives is likely to have offspring.
Sent 14: If it does, it may pass the new trait on to its offspring.
Sent 15: Thats good news for the offspring.
Sent 16: The offspring may be more likely to survive.
Sent 17: Mutations are one way living things adapt to new conditions.
Question: Are mutations harmful or natural?.

A: 4, 5.
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Q: Paragraph- Sent 1: Electric current cannot go through empty space.
Sent 2: Electricity needs something to flow through.
Sent 3: Electricity cannot flow through all materials.
Sent 4: Some materials resist the flow of electricity.
Sent 5: Some materials let electricity pass through easily.
Sent 6: Scientists classify these into two groups.
Sent 7: These groups are called conductors and insulators.
Sent 8: Materials that allow electrons to flow freely are called electric conductors.
Sent 9: Electricity is able to race through these materials.
Sent 10: Copper, aluminum, and steel are good conductors.
Sent 11: Materials that resist the flow of electricity are called electric insulators.
Sent 12: Instead of racing, the current may travel in slow motion, if at all.
Sent 13: Wood, rubber, and plastic are examples of electric insulators.
Sent 14: You probably know that electric wires are made of metal.
Sent 15: They typically have a rubber or plastic coating.
Sent 16: Do you know why?
Sent 17: Metals are good electric conductors.
Sent 18: They offer little resistance to electricity.
Question: What are conductors and insulators?.

A:
8, 11.
****