In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

Q: Question: What is defined as the velocity of the object at a given moment? Answer: instantaneous velocity

A: Instantaneous velocity is defined as the velocity of the object at a given moment.
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Q: Question: When blood vessels in the head dilate, what kind of severe headache can occur? Answer: migraine

A: When blood vessels in the head dilate, a migraine, a severe headache, can occur.
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Q: Question: What do concentric circles on a topographic map indicate? Answer: a hill

A:
A hill do concentric circles on a topographic map indicate.
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