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: A student should use a balance to compare the masses of two small rocks.

A: Which tool should a student use to compare the masses of two small rocks?
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Q: The female reproductive system consists of structures that produce eggs, secrete female sex hormones, and ultimately enable birth of a fetus.

A:
What system consists of structures that produce eggs, secrete female sex hormones, and ultimately enable birth of a fetus?
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