Problem is attached

Problem is attached 

a)which scheduling rule is the most appropriate for saving all five scuba dives successfully and why?

b)in what sequence should the jobs be processed according to the scheduling rule you have determined in part a above?

c)with the job sequence you have determined in part b above, what is the average number of jobs in the system for completing all jobs?

d)with the job sequence you have determined in part b above, what is the utilization for this case?