Given a statement, generate a question such that the answer is contained in that statement.

Q: FM systems are used for entertainment

A: What are used for entertainment?
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Q: a directory of the types of hemoglobin in the family tree is a useful tool for studying inheritance patterns

A: What is a useful tool for studying inheritance patterns?
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Q: an abacus is used for multiplication

A:
What is an abacus used for?
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