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.
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Question: Category: U.S. PRESIDENTS 
Clue: During his tenure, he never threw out an opening day first pitch, but before he was president, he did it for the Braves

Answer: jimmy carter


Question: Category: ROMAN EMPERORS 
Clue: In 59 A.D. Agrippina wrote to this man, her son, "Tell me why I should plot against your life?"--she was killed anyway

Answer: nero


Question: Category: CANALS 
Clue: When Sweden's Gota Canal was completed in the 1820s, these 2 seas became directly linked

Answer:
the baltic sea & the north sea