$3-$ Suppose the following processes arrive for execution at the times indicated below. Use non$-$preemptive scheduling to answer the questions below

Process Arrival Time Burst Time

P$108$

P$20\mathrm{.}44$

P$31\mathrm{.}01$

a$.$ What is the average turnaround time for these processes with the FCFS scheduling algorithm

b$.$ What is the average turnaround time for these processes with the SJF scheduling algorithm