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

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: Solid is characterized by molecules with minimal movement and strong forces between them.

A: Which state of matter is characterized by molecules with minimal movement and strong forces between them?
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Q: Hormones generally travel through the circulatory system system of the body.

A:
Through what system of the body do hormones generally travel?
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