Given an trivia question precisely answer the question with a word/phrase/name. External resources such as Wikipedia could be used to obtain the facts.
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Question: Derived from the Greek word meaning perimeter, what is the text form of the sixteenth letter of the Greek alphabet?

Answer: pi

Question: Who is the famous mother of Elijah Blue?

Answer: cher

Question: Which of the Marx brothers was the silent one?

Answer:
harpo