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 episode does grey's anatomy have a shooting?

Answer: Death and All His Friends


Question: Are radio waves electromagnetic waves or sound waves?

Answer: electromagnetic waves


Question: What type of government system does the usa have?

Answer:
federal republic