a. Perform the same type of analysis as that of Table for the following sequence of disk track requests: 27, 129, 110, 186, 147, 41, 10, 64, 120. Assume that the disk head is initially positioned over track 100 and is moving in the direction of decreasing track number.

b. Do the same analysis, but now assume that the disk head is moving in the direction of increasing track number.

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(c) SCAN (starting at track 100, in the direction of increasing track number) (d) C-SCAN (starting at track 100, in the direction of increasing track number) (a) FIFO (starting at track 100) (b) SSTF (starting at track 100) Number Next track of tracks Next track of tracks Next track of tracks Next track of tracks accessed raversed Number traversed 10 32 Number Number accessed accessed 90 58 accessed 150 160 184 90 58 traversed traversed 58 39 18 90 160 150 38 184 50 10 24 94 32 150 160 184 18 38 39 50 10 24 166 20 19 21 72 70 39 38 18 150 160 184 Average seek length 16 20 132 10 24 275 39 38 18 Average seek length 16 16 112 58 146 20 32 Average seek length 55.3 278 Average seek length 35.8