4. Consider the following set of processes, with the length of the CPU burst given in milliseconds: (25) Score Process Arrive Time Burst Time Priority P 0 8 3 P2 0 5 2 P; 1 4 5 P 1 6 4 PS 2 2 1 (1). Draw four Gantt charts that illustrate the execution of these processes using the following scheduling algorithms: FCFS, SJF (non-preemptive). preemptive priority (a smaller priority number implies a higher priority), and RR (Quantum = 2) (15') (2). Calculate the turnaround time and the waiting time of each processes for each of these scheduling algorithms? (6) (3). Which algorithm results in the minimum average waiting time (over all processes)? (4")