3 Ambulance Staffing. Suppose ambulance drivers are not allowed to drive for more than 3 trips in a shift. The shifts at an ambulance station are 12-8AM, 8AM-4PM, 4PM-12AM. We will assume ambulance requests can be represented using a non-homogeneous Poisson process. The intensity function for that indicates the number of 911 calls received is as follows, where t indicates the hours in a day (i.e. t = 16 at 4PM): 4 0