Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Q: Herbivores is the term for animals that eat producers to get energy.

A: What is the term for animals that eat producers to get energy?
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Q: Renewable energy sources emit fewer or no greenhouse gases.

A: What type energy sources emit fewer or no greenhouse gases?
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Q: Mechanical waves term describes waves that travel through matter.

A:
What term describes waves that travel through matter?
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