suppose that a disk drive has 5000 cylinders,numbered 0 to 4999.head position is at 143,previous request is 125.the queue in pending request in fifo order is 86,1470,913,1774,948,1509,1022,1750,130.starting from head position by usinga.fcfsb.sstfc.scand.looke.c-scanf.c-look
