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: DRAMA 
Clue: Sula & Helena are robotesses in this Karel Capek play

Answer: "r.u.r."


Question: Category: HEAVY MACHINERY 
Clue: By definition it's a machine that gives a surface an even degree of slope

Answer: grader


Question: Category: PROPHECIES & PREDICTIONS 
Clue: Known as "The Sleeping Prophet", in 1941 he predicted NYC would be destroyed near the year 2000

Answer:
edgar cayce