Four jobs to be executed on a single processor system arrive at time 0+ in the order A, B, C, D. their burst CPU time requirements are 4, 1, 8, 1 time units respectively. The completion time of A under round robin scheduling with time slice of one time unit is
0 1 2 3 4 5 6 7 8 9
I am not complete all gantt chart entry . because of questions asked only Completion time of A.