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\*.
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Question: when did justin bieber perform at madison square garden

Answer: August 31, 2010


Question: what is the microscopic unit of the kidney

Answer: The nephron


Question: who determined that all animals are made of cells

Answer:
Robert Hooke