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

Q: Millibar is the unit used to measure air pressure.

A: What is the unit used to measure air pressure?
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Q: Phototaxis is the term for movement toward light.

A: What is the term for movement toward light?
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Q: Co 2 is the molecular formula of carbon dioxide.

A:
What is the molecular formula of carbon dioxide?
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