11 From historical data, Harry’s Car Wash estimates that dirty cars arrive at a rate of 10 per hour all day Saturday. With a crew working the wash line, Harry figures that cars can be cleaned at a rate of one every five minutes. One car at a time is cleaned in this example of a single-server waiting line.

Assuming Poisson arrivals and exponential service times, find the

(a) average number of cars in line

(b) average time a car waits before it is washed

(c) average time a car spends in the service system

(d) utilization rate of the car wash

(e) probability that no cars are in the system