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: what were the cause of the american civil war

A: conflicts over slavery
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Q: who played in the men's semi final in wimbledon in 2015

A: Novak Djokovic
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Q: where is new year's eve celebrated first

A:
Tonga
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