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: Urea is made in the liver and excreted in urine.

A: What is made in the liver and excreted in urine?
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Q: Under appropriate conditions, the attractions between all molecules in gas state will cause them to form liquids or solids.

A:
Under appropriate conditions, the attractions between all molecules in what state will cause them to form liquids or solids?
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