please answer

2. 12-11 The Rockwell Electronics Corporation retains a service crew to repair machine breakdowns that oc- cur on an average of A = 3 per day (approximately Poisson in nature). The crew can service an average of M = 8 machines per day, with a repair time distribution that resembles the exponential distribution. (a) What is the utilization rate of this service sys- tem? (b) What is the average downtime for a machine that is broken? (c) How many machines are waiting to be serviced at any given time? (d) What is the probability that more than one machine is in the system? Probability that more than two are broken and waiting to be repaired or being serviced? More than three? More than four