In this task, you're given an ambiguous question (which can be answered in more than one way). Your task is to write a question that clarifies the given question in such a way that the generated question has one unique answer.
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Question: Why would a recrystallization need to be done?

Answer: Why would recrystallization need to be done in chemistry?


Question: Where are most of the us oil refineries located?

Answer: Where with respect to geographical features are most of the us oil refineries located?


Question: When is the last time the cleveland browns made the playoffs?

Answer:
How many years ago is the last time the cleveland browns made the playoffs?