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: Who wrote sitting by the dock of the bay?

A: Otis Redding and Steve Cropper
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Q: How much money does tourism bring to canada?

A: $17.4 billion
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Q: Which of the following country has madrid as it's capital?

A:
Spain
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