Write a correct answer to the given question based on its associated fact. Make sure that your answer is contained in the associated fact. Don't be creative and introduce any new word that is not mentioned in the associated fact! Remember that the associated fact has been rearranged to form the question. So, the correct answer words must lie within the associated fact. The correct answer can be a word, phrase, or even a sentence.

Q: Fact: diatomes have varied life cycles. 
Question: what have varied life cycles?

A: diatomes.
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Q: Fact: bears hibernate to conserve energy. 
Question: Why do bears hibernate?

A: conserve energy.
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Q: Fact: Veins carry blood that is heavy with carbon dioxide. 
Question: What is blood heavy with?

A:
Carbon dioxide.
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