In this task, You are given an open-domain question that can be answered based on factual information. Your task is to provide \*short\* answer (in a few words only) for the given question. The short answer can be one or more entities or it can also be boolean \*yes\* or \*no\*.

Q: when did drinking age go from 18 to 21

A: mid-1988
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Q: when was the dubai metro green line opened to public

A: September 2011 (
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Q: who does the voice of optimus prime in the transformers

A:
Peter Claver Cullen
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