1. Cars arrive at a car wash fandomly and independently; the probability of an arrival is the same for any two time intervals of equal length. The mean arrival rate is 15 cars per hour.

what is the probability that 20 or more cars will arrive during any give hour of operation?

2. A deck of playing cards contais 52 cards, four of which are aces. What is th e probability that the deal of a five – card hand provides:

a. A pair of aces?

b. Exactly ONE ace?

c. No aces?

d. At least one ace?