Austin has three pairs of pants: a black pair, a navy blue pair, and a tan pair. He also has two polo shirts: a red shirt and a purple shirt. If Austin randomly selects one pair of pants and one polo shirt from his wardrobe:

a. how many different outfit combinations can he create?

b. Draw a Tree Diagram illustrating this.

c. Find the probability of selecting black pants (so the shirt type doesn't matter)

d. Find the probability of selecting tan pants and a red shirt

e. Find the probability of selecting a red shirt (so the pant type doesn't matter)