Let X be the length in inches of curtains sold by Cal Curtains and it can take values 129, 130 and 131. Let Y be the width in inches of curtains and it can take values 15 and 16. The joint probability function for X and Y are given in the table below:

	129	130	131
15	0.12	0.42	0.06
16	0.08	0.28	0.04

a) What is the probability that a randomly chosen curtain has a length of 130 inches?

b) What is the expected length of curtains sold by Cal Curtains?

c) What is the variance in the width of curtains sold by Cal Curtains?