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: Which unit is used to express the amount of energy in food? Answer: Calorie

A: A calorie is used to express the amount of energy in food.
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Q: Question: When magma reaches the surface through cracks in the earth's crust, what occurs? Answer: volcanic eruption

A: When magma reaches the surface through cracks in the earth's crust, a volcanic eruption occurs.
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Q: Question: What does interstellar medium consist of? Answer: thinly spread gas and dust

A:
Interstellar medium consists of thinly spread gas and dust.
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