Arrivals of customers at a telephone booth follow the Poisson distribution, with an average time of 10 minutes between one arrival and the next. The phone call length is assumed to be exponentially distributed with a mean of 3 minutes. Find: a) The average number of persons waiting and making telephone calls b) The average length of the queue that is formed from time to time c) The probability that a customer arrives and finds a telephone booth is busy. d) Probability that a customer arrives and finds the telephone booth empty. Question 4 (12 marks) Consider the following 4 workstation production lines. a) What are the workstation processing rates? b) What is the bottleneck rate? c) What is the raw processing time? d) What is the critical WIP for the system? e) What is the individual workstation WIP value