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

Q: Gastro-esophageal sphincter sphincter is located at the stomach end of the esophagus and opens to allow the bolus to enter the stomach.

A: Which sphincter is located at the stomach end of the esophagus and opens to allow the bolus to enter the stomach?
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Q: You see a faster reaction rate when the concentration of reactants is higher.

A: What kind of reaction do you see when the concentration of reactants is higher?
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Q: Maritime air type of air may get stuck on the windward side of a mountain range.

A:
What type of air may get stuck on the windward side of a mountain range?
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