Uh... or your knowledge of Americana. Needless to say I failed on:
8) 13 = Stripes of the American Flag
9) 32 Degrees Fahrenheit at which Water Freezes
12) 200 = Dollars for Passing Go in Monopoly
18) 5 = # of Digits in a Zip Code
19) 57 = Heinz Varieties
20) 11 = Players on a Football Team
and got most of the others.
Later dudes,
-- Rob.
PS: It was fun looking for nonsense/gross answers!