A moving-head disk has 200 tracks, numbered 0 to 199. The head has just finished a request at track 125 and is currently at track 143 (so it is moving in the direction of increasing track numbers). The pending request queue, in FIFO arrival order, is: 86, 147, 91, 177, 94, 150, 102, 175, 130. What is the total head movement (in cylinders) to service all these requests using the SCAN algorithm?
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Correct answer: B. (B) 169 cylinders
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