3. CPU Scheduling (40 points) Assume some OS needs to schedule four processes using different scheduling algorithms. For each process, the following table shows its burst time (processing time), priority (The lower the number, the higher the priority), and arrival time. Processes P1 P2 P3 P4 Burst Time 12 Priorittv Arrival Time 18 Table 1. Process Information Questions: What is the Average Waiting Time of those processes for each of the following schedule algorithms? (Draw a Gantt Chart for each algorithm.) 1) First Come First Serve (FCFS) 2) Non-preemptive Shortest Job First (NP-SJF) 3) Preemptive Shortest Job First (P-SJF) 4) Priority Scheduling 5) Round-Robin (Assumptions 1: The scheduling time quantum is 5 time units. Assumption 2: If a new processives at the same time as the time slice of the executing process expires, the OS puts the executing process to the ready queue, followed by the new process.)