Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Chemical digestion mainly occurs in the small intestine.

Answer: Where does chemical digestion mainly occur?


Question: Population is an important level of organization in ecology and the unit of microevolution.

Answer: What is an important level of organization in ecology and the unit of microevolution?


Question: The water in some springs are hot because they're heated by hot magma.

Answer:
The water in some springs are hot because they're heated by what?