Assume three jobs arrive at approximately the same time (arrival time are all 0), but Job A arrives slightly before Job B, and Job B arrives slightly before job C (if the jobs must be selected in order, the order should be A->B->C). Job A requires 2 sec of CPU, Job B is 8 secs, and Job C is 7 secs. Assume a time-slice of 1 second. Given a RR scheduler (time slice is 1sec), what is the average response time of the three jobs?