One operator services a bank of five machines. Machine running and service times are both exponential. Machines run for an average of 180 minutes between service requirements, and service time averages 60 minutes. The operator receives $20 per hour in salary and fringe benefits, and machine downtime is $70 per hour.
a) If each machine produces 60 pieces per hour while running, find the hourly output of each machine, when waiting and service times are taken into account.
b) What is the average amount of time (in minutes) that a machine has to wait before being serviced by the operator?
	97.08
c) Determine the optimum number of operators.			2 servers
	at 2 servers it provides the lowest total cost of the 3 options (=139.3125)
Copy and paste onto this worksheet the output used in anwering the questions above.
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	Finite Source Waiting Line Model
		Population Size	N =	5	5	5
		Number of servers	M =	1	2	3
		Average service time	T =	60	60	60
		Average time between service calls	U =	180	180	180
		P(wait) - from table	D =	0.8900	0.2840	0.0520
		Efficiency factor - from table	F =	0.7120	0.9550	0.9950
		Service factor	c =	0.250	0.250	0.250	#DIV/0!
		Average number waiting	L =	1.4400	0.2250	0.0250	0.0000
		Average waiting time	W =	97.0787	11.3089	1.2060	#DIV/0!
		Average number running	J =	2.6700	3.5813	3.7313	#DIV/0!
		Average number being serviced	H =	0.8900	1.1938	1.2438	#DIV/0!
			Per Time
			Unit
		Service cost =	20	20	40	60	0
		Downtime cost =	70	163.1	99.3125	88.8125	#DIV/0!
		Total Cost =		183.1	139.3125	148.8125	#DIV/0!
		Note: You must enter D and F (based on N, C, and M) from the table in the text.

A= 32.04

Please give a detailed explanation on how to solve A.