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: SCIENCE 
Clue: What you're "stuck with" boiling down collagen, softening it with hot water & letting it swell
[A]: glue


[Q]: Category: SPORTS TALK 
Clue: In a game of tennis, deuce is the same as 3 points all, which is called this tie score
[A]: 40-to-40


[Q]: Category: HISTORIC GEOGRAPHY 
Clue: By 900 A.D. Harold Fairhair had become the first king of this Scandinavian nation
[A]:
norway