In this task, you are given a sentence and a question, you would be asked to create the answer which is contained in the sentence provided.
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Question: Sentence: Sun does the stratosphere get most of its heat. Question: Where does the stratosphere get most of its heat?

Answer: sun


Question: Sentence: A moving car is said to be in dynamic equilibrium when it is zero net force. Question: When is a moving car said to be in dynamic equilibrium?

Answer: zero net force


Question: Sentence: A(n) increase in length happens to metal railroad tracks during the heat of a summer day. Question: What happens to metal railroad tracks during the heat of a summer day?

Answer:
increase in length