In this task, you're given an open-domain question. Your task is to provide an answer to the given question. There is only one unique answer for each question. Your answer should be short, and refer to an entity, date, number, etc. Do not put your answer in the context of a sentence.

Q: When does arrow season 6 air on tv?

A: October 12, 2017
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Q: When did the last episode of seinfeld air?

A: May 14, 1998
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Q: What is the term for the amount of time it takes 50 of an element to decay?

A:
half life
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