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: Where was the first mcdonald's in phoenix built?

A: Central Avenue and Indian School Road
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Q: What branch of biology creates models to make whole biological systems understandable?

A: computational systems biology, systems biology and mathematical biology
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Q: Rutherford scattering experiment is related to the size of?

A:
nucleus
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