2.28 Socks in a drawer:  In your sock drawer you have 5 blue, 5 gray, and 2 black socks. Half asleep one morning you grab 2 socks at random and put them on. Find the probability you end up wearing
(Keep three decimal places.)

a) 2 blue socks
b) no gray socks
c) at least 1 black sock
d) a green sock
e) matching socks