During the verif cation process of the airline check-in system from Exercise 4-3, it was discovered that there were really two types of passengers. The f rst passenger type arrives according to an exponential interarrival distribution with mean 2.41 minutes and has a service time (in minutes) following a gamma distribution with parameters ! 5 0.42 and " 5 14.4. The second type of passenger arrives according to an exponential distribution with mean 4.4 minutes and has a service time (in minutes) following 3 plus an Erlang distribution with parameters ExpMean 5 0.54 and k 5 15 (that is, the Expression for the service time is 3 1 ERLA(0.54, 15)). A passenger of each type arrives at time 0. Modify the model from Exercise