Problem 18-5 A small town with one hospital has 2 ambulances to supply ambulance service. Requests for ambulances during nonholiday weekends average .50 per hour and tend to be Poisson-distributed. Travel and assistance time averages 2 hours per call and follows an exponential distribution Use Table 1. a. Find system utilization. (Round your answer to the nearest whole percent. Omit the "%" sign in your response.) System utilization b. Find the average number of customers waiting. (Round your answer to 3 decimal places.) Average number of customers c. Find the average time customers wait for an ambulance. (Round your answer to 3 decimal places.) Average time hour d. If there are 2 ambulances, find the probability that all ambulances will be busy when a call comes in. (Round intermediate calculations to 3 decimal places and final answer to 2 decimal places.) Probability