You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Q: Category: MEN OF SCIENCE 
Clue: On a scale of 1 to 10, his "Earthquakes" article for the 15th edition of Encyclopedia Britannica was a 10

A: richter
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Q: Category: MAGIC 
Clue: 2-word "conjuring" brand name for a felt-tip pen that comes in many colors

A: magic marker
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Q: Category: MOZART & FRIENDS 
Clue: Mozart wrote a lovely motet for Venanzio Rauzzini, one of these specially treated singers

A:
a castrato
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