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: CIVIL WAR SITES 
Clue: Of the 6 Civil War-related national military parks, the northernmost & southernmost are in these 2 states

A: pennsylvania & mississippi
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Q: Category: INVENTORS 
Clue: Mainz, Germany celebrates the life of this inventor in an annual festival called Johannisnacht

A: johannes gutenberg
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Q: Category: U.S. LANDMARKS 
Clue: It contains over 5,000 tons of steel, rises 630 feet in the air & is in the shape of an inverted catenary curve

A:
the st. louis gateway arch
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