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 played roxy in the story of tracy beaker?

A: Sophie Borja
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Q: Where does implantation of the blastocyst take place?

A: wall of the uterus
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Q: An astronomical object that generates energy through nuclear fusion is a?

A:
a star
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