Problem: Computer Simulation

Jack Williams operates a small mechanics shop in his hometown, Lima, Ohio. He works six days a week, Monday thru Friday, $10$:$00$ AM to $6$:$00$ PM and Saturdays from $9$:$00$ AM to $12$:$00$ PM$.$ On a regular weekday, customers$$ arrival time is exponentially distributed with a mean of $45$ minutes and service time is also exponentially distributed with a mean of $35$ minutes. Simulate Jack Williams$$ shop for $100$ customer arrivals to estimate Average Time in Line and Average Time in System.