Vehicles begin to arrive at a remote parking lot after the start of a major sporting event. They are arriving at a deterministic but time-varying rate of "3.3-0.1t" where 't' is in minutes. the parking lot attendant processes vehicles ( collects fee and assigns spaces) at a deterministic rate at a single station. A queue exceeding 4 vehicles will back up onto a congested street and is to be avoided. how many vehicles per minute must the attendant process to ensure that the queue does not exceed 4 vehicles?