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

Q: While the numerical aperture can be used to compare resolutions of various objectives, it does not indicate how far the lens could be from the specimen.

A: While the numerical aperture can be used to compare resolutions of various objectives, it does not indicate how far the lens could be from the what?
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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: It is liquid at most temperatures on earth property of water is most important for living organisms.

A:
What property of water is most important for living organisms?
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