A box contains 5 red and 5 blue marbles. Two marbles are withdrawn randomly. If they are

Question:

A box contains 5 red and 5 blue marbles. Two marbles are withdrawn randomly. If they are the same color, then you win $1.10; if they are different colors, then you win −$1.00. (That is, you lose $1.00.) Calculate
(a) The expected value of the amount you win;
(b) The variance of the amount you win.