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

Q: The combustion of propane gas produces carbon dioxide and water vapor.

A: The combustion of propane gas produces carbon dioxide and what else?
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Q: Duplicating the results of an experiment process will most likely lead to the scientific acceptance of a hypothesis.

A: Which process will most likely lead to the scientific acceptance of a hypothesis?
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Q: Precipitation and runoff in the water cycle are primarily responsible for the creation of a lake.

A:
Which two processes in the water cycle are primarily responsible for the creation of a lake?
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