• Consider the following workload: Process Burst Time (ms) Priority Arrival Time P1 50 4 0 ms P2 20 1 20 ms P3 100 3 40 ms P4 40 2 60 ms a. Draw three Gantt charts that illustrate the execution of these processes using the following scheduling algorithms: shortest remaining time, nonpreemptive priority (a smaller priority number implies higher priority) and round robin with quantum 30 ms. b. What is the average waiting time of the above scheduling policies?