Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: tobacco smoke causes fatal lung disease in nonsmokers. Answer: tobacco smoke

A: What still causes fatal lung disease in nonsmokers?
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Q: Passage: Volatile organic compounds (VOCs) are carbon compounds such as methane. VOCs are released in many human activities, such as raising livestock. Livestock wastes produce a lot of methane. Answer: methane

A: The waste of cows releases a lot of which type of gas?
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Q: Passage: An ecosystem consists of all the living things and nonliving things interacting in the same area. Answer: ecosystem

A:
What consists of all the living things and nonliving things interacting in the same area?
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