Q22) (Input / Output) Disk requests come in to the disk driver for cylinders 10, 22, 20, 2, 40, 6, and 38, in that order. A seek takes 6 msec per cylinder. How much seek time is needed for:

(a) First-come, first served.

(b) Closest cylinder next.

(c) Elevator algorithm (initially moving upward).

In all cases, the arm is initially at cylinder 20.