One mechanic services 5 drilling machines for a steel plate manufacturer. Machines break down on an average of once every 6 working days, and breakdowns tend to follow a Poisson distribution. The mechanic can handle an average of one repair job per day. Repairs follow an exponential distribution.

(a) How many machines are waiting for service, on average?

(b) How many are in the system, on average?

(c) How many drills are in running order, on average?

(d) What is the average waiting time in the queue?

(e) What is the average wait in the system?