$9.$ For the output: Each customer process should write three lines to the screen, at the following times: $1.$ When they arrive at the bank and enter the waiting line. $2.$ When they step up to a teller and start being served. $3.$ When they finish being served by a teller and leave the bank. Each line consists of the current simulated world time, identifying the customer by number, and the appropriate message. Finally, at the end of the simulation print a summary message, giving: $1.$ The total number of customers served. $2.$ The average time spent waiting in line by the customers served. The output of a sample run of the program: Mean inter$-$arrival time: $10$ Mean service time: $30$ Number of tellers: $3$ Length of simulation: $70$ At time $30,$ customer $1$ arrives in line At time $30,$ customer $1$ starts being served At time $30,$ customer $2$ arrives in line At time $30,$ customer $2$ starts being served At time $30,$ customer $3$ arrives in line At time $30,$ customer $3$ starts being served At time $40,$ customer $1$ leaves the bank At time $50,$ customer $4$ arrives in line At time $50,$ customer $4$ starts being served At time $50,$ customer $4$ leaves the bank At time $50,$ customer $5$ arrives in line At time $50,$ customer $5$ starts being served At time $50,$ customer $6$ arrives in line At time $50,$ customer $7$ arrives in line At time $60,$ customer $3$ leaves the bank At time $60,$ customer $5$ leaves the bank At time $60,$ customer $6$ starts being served At time $60,$ customer $7$ starts being served At time $70,$ customer $7$ leaves the bank