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: AMERICAN ARTISTS 
Clue: From 1919 to 1924, this artist taught art in the public schools of Cedar Rapids, Iowa

A: grant wood
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Q: Category: SCIENTIFIC MNEMONICS 
Clue: "Kings play chess on finely grained sand" is a mnemonic device used to help remember a system devised by this scientist

A: carolus linnaeus
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Q: Category: LANDMARKS 
Clue: Popular name for the Jefferson Nat'l Expansion Memorial

A:
gateway arch
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