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.
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Question: What does code 11 mean in an airport?

Answer: Late check-in, acceptance of passengers after deadline


Question: Who has the longest field goal in the nfl?

Answer: Matt Prater


Question: When did water fluoridation begin in the uk?

Answer:
1964