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: MEN OF SCIENCE 
Clue: On a scale of 1 to 10, his "Earthquakes" article for the 15th edition of Encyclopedia Britannica was a 10

A: richter
****
Q: Category: THE 1970s 
Clue: In 1977 Bank of America changed the name of its Bank Americard to this 4-letter word

A: visa
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Q: Category: SLEEPY 
Clue: Big Arm, Bigfork, & Big Sky are all little towns in this state

A:
montana
****