Promodel View Text file of Visitors arrive at Kid's World entertainment park according to an exponential inter-arrival time distribution with a mean of 2.5 minutes. The travel time from the entrance to the ticket window is normally distributed with a mean of 3 minutes and a standard deviation of 0.5 minutes. At the ticket window, visitors wait in a single line until one of four cashiers is available to serve them. The time for the purchase of tickets is normally