Question

I am stuck on the whole problem because I do not understand how to work them out per my textbook explanation

A grab bag contains 11 $1.00 prizes, 8 $5.00 prizes and 3 $20.00 prizes. If three prizes are chosen at random, find the probabilities.

The probability that exactly two $20 prizes are chosen is?
The probability that one of each prize is chosen is?
The probability that at least one $20 prize chosen is?
The probability that no $1 prizes are chosen is?

(Round to the nearest thousandth as needed)