The MLFQ (Multi-Level Feedback Queue) scheduler has a set of rules used to achieve different goals. Consider an MLFQ scheduler with 5 queues (Q1 to Q5) with Q1 being the lowest-priority queue and Q5 being the highest priority queue. You can assume a 1-processor system (i.e., 1CPU ), time slice =10ms, and that job A takes 100ms to complete. Answer questions 7 to 12 Question 7 5pts In what queue is job A placed when it first arrives? Q5 Q2 Q4 Q3 Q1 Assume that job A is CPU-bound (i.e., not interactive), in what queue it will be located 35ms after it arrives? Q1 Q2 Q4 Q3 Q5 Question 9 6 pts Assuming no boosting and that job A doesn't do any I/O and continues executing until it finishes. How many milliseconds (ms) does it spend in Q1 before finishing? \begin{tabular}{|c} \hline 75ms \\ \hline 60ms \\ \hline 10ms \\ \hline 40ms \\ \hline 100ms \end{tabular} Assume 2 CPU-bound short jobs arrive at the same time (B and C each requiring 15ms to finish). You can assume that B arrives a hair before C and the scheduler runs it before C. In what queue will B be when it finishes? Q4 Q3 Q2 Q5 Q1 Question 11 4 pts After jobs B and C finish, a new job D arrives and immediately starts doing I/O every 9 ms where each I/O lasts 1ms. Assuming no time allotment, in what queue will job D be 30ms after it arrives? Q2 Q4 Q5 Q3 Q1 For jobs that continuously do I/O, what mechanism does MLFQ employ to prevent such jobs from abusing the system and remaining in higher priority queues? Boosting Put the job in a queue that the OS reserves for jobs trying to abuse the system. Demote the job to the lowest priority queue (Q1) irrespective of where it is. Demote the job to to the next lower priority queue after some time alotement Promote the job to a higher priority queue