Today 9:01 AM automotive repair shop has a part department to store and provide parts to mechanics. The number of mechanics come in to the part department per hour is a Poisson random and the mean is 6. Currently there is two clerks working in front desk. Each of them can serve mechanics with mean 12 minutes service time (exponential) 29. (5 points) Find system utilization. (Round your answer to 1 decimal point in percent.) 30. (10 points) Find the average number of mechanics waiting (in line). 31. (10 points) Find the average time mechanics spending in the part department 32. (15 points) The manager considers hiring one more clerk to reduce the waiting time of mechanics. The hourly wage of a clerk is $ 25 and that of mechanics is $50. Is hiring the third clerk econortical? How much would be the change (difference) of total cost ( clerk and mechanics) per hour from two to three clerks ?