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 consistency, answers should be in all lower cased letters.

Q: Category: FILTHY RICH 
Clue: Worth over $15 billion, Robson, son of Sam, runs this company, the USA's largest private employer

A: wal-mart
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Q: Category: SLEEP 
Clue: Normally this activity is harmless, but make sure the person doesn't fall down the stairs

A: sleepwalking
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Q: Category: CLIFF NOTES 
Clue: Before "Into the Wild", this author wrote "Into Thin Air", about a Mount Everest trip gone wrong

A:
jon krakauer
****