Return to the credit card scenario of exercise 12 (section  2.2), and let c be the event that the selected student has an american express card. in addition to p(a) = .6, p(b) = .4, and p(a >
b.= .3, suppose that p(c) = .2, p(a  > c)  = .15, p(b >
c.= .1, and p(a > b >
c.= .08.
a. what is the probability that the selected student has at least one of the three types of cards?
b. what is the probability that the selected student has both a visa card and a mastercard but not an american express card?
c. calculate and interpret p(b u
a. and also p(a u b).