13. The University of Oregon's football team has many different uniforms. The coach can choose from four colors of Jerseys and
pants: green, yellow, white, and black. There are three helmet
options: green, white, and yellow. Also, there are the same four
colors of socks and two colors of shoes, black and yellow.
a. How many jersey/pant combinations are there?
b. If the coach picks a jersey/pant combination at random, what is
the probability he will pick a yellow jersey with green pants?
c. Use a tree diagram to find all of the possible shoe and sock
combinations.