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

Q: Rainfall weather phenomenon increases the rate of weathering in rock and soil.

A: What weather phenomenon increases the rate of weathering in rock and soil?
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Q: Temperature and ph level are important in the activity of an enzyme.

A: Temperature and what other environmental factor are important in the activity of an enzyme?
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Q: When it bursts do weather balloons return to earth.

A:
When do weather balloons return to earth?
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