4 If 2 sin X = 1 (where X is the measure of an acute angle), then X = (a) 45°
(b) 90°
(c) 30°
(d) 60°

Suppose that a disk drive has 5,000 cylinders, numbered 0 to 4,999. the drive is currently serving a request at cylinder 2,150, and the previous request was at cylinder 1,805. the queue of pending requests, in fifo order, is: 2069, 1212, 2296, 2800, 544, 1618, 356, 1523, 4965, 3681