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

Q: Resistors connected end to end are said to be in series.

A: Resistors connected end to end are said to be in what?
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Q: Seismologists originally measured the intensity of an earthquake with the mercalli scale.

A: How did seismologists originally measure the intensity of an earthquake?
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Q: Population is the term for individuals of a species that live in a particular habitat.

A:
What is the term for individuals of a species that live in a particular habitat?
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