Elatively high volume in winter months. the service rate of a postal clerk is 0.75 customers per minute. the post office counter has a maximum of three workstations. the target maximum time a customer waits in the system is 5 minutes. for a particular monday morning, the anticipated arrival rate is 1.3 customers per minute. assume two out of three workstations are open. with an expected growth to 2.1 customers per minute, the corresponding wait time in the system (3 decimal places) is