The press department of an automobile manufacturing facility runs two main operations, each with its own press machine: front-plate press operation and rear-plate press operation. These operations can be performed in any order, but both have to be performed for each arriving plate. Plates (jobs) arrive randomly and their interarrival times are exponentially distributed with mean 5 minutes. The service time in the front-plate press operation is distributed iid UNIF(1, 5) minutes, and in the rear-plate press operation it is distributed iid UNIF (2, 6) minutes. A plate joins the queue of the press operation with the least number of plates waiting at that time (since there is no sequencing requirement), and on completion joins the queue of the other press operation after which it departs from the system. Finally, the press department is a three-shift facility running 24 hours a day.

1) Develop an Arena model of the press department, and simulate it for one year.

2) Estimate the following statistics:

a) Average time arriving plates spend in the press department

b) Utilization of the press machine in each operation

c) Average queue delay at each operation

d) Average time in the press department of those arriving plates that join first the rear-

plate press operation, and then proceed to the front-plate press operation