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

Q: One of the properties of an air mass is that an air mass has similar temperature and moisture properties throughout it.

A: Which of the following is true regarding the properties of an air mass?
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Q: The name of film that polyester fibers form is mylar.

A: What is the name of film that polyester fibers form?
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Q: The concentration of hydrogen ions in a solution is called acidity.

A:
The concentration of hydrogen ions in a solution is called?
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