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The Garrett-Tompkins Company provides three copy machines in its copying room for the use of its employees. However, due to recent complaints about considerable time being wasted for a copier to become free, management is considering adding one or more additional copy machines. During the 2000 working hours per year, employees arrive at the copying room at a mean rate of 32 per hour and it is assumed to be exponentially distributed. The time each employee needs with a copy machine is believed to have an exponential with a mean of 4 minutes. Use the excel format and 1. Find waiting time in the queue and system 2. Find number of customers in the queue and system 3. Find the probability of finding exactly three customers in the system 4. Find the probability that the waiting time in the queue exceed 8 minutes 5. The lost productivity due to an employee spending time in the copying room is estimated to cost the company an average of $25 per hour. Each copy machine is leased for $3000 per year. Determine how many copy machines the company should have to minimize its expected total cost per hour