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: The cubic crystal system is composed of how many different types of unit cells? Answer: three

A: The cubic crystal system is composed of three many different types of unit cells.
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Q: Question: Carbon dioxide does not rise like other gases because it has a density greater than what? Answer: air

A: Carbon dioxide does not rise like other gases because it has a density greater than air.
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Q: Question: What is the term for dry climate regions at higher altitudes that have short grasses and low bushes? Answer: steppes

A:
Steppes is the term for dry climate regions at higher altitudes that have short grasses and low bushes.
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