A disk has tracks from 0 to 179. Currently the head is at track 40. The R/W requests for tracks are in the following order- 80, 102, 26, 160, 35, 10, 135. What is the total head movement when SSTF algorithm is used?

A disk has tracks from 0 to 179. Currently the head is at track 40. Th

1.	A disk has tracks from 0 to 179. Currently the head is at track 40. The R/W requests for tracks are in the following order- 80, 102, 26, 160, 35, 10, 135. What is the total head movement when SSTF algorithm is used?
A.	180
B.	190
C.	258
D.	542
Answer» B. 190

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A disk has tracks from 0 to 179. Currently the head is at track 40. The R/W requests for tracks are in the following order- 80, 102, 26, 160, 35, 10, 135. What is the total head movement when SSTF algorithm is used?
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A disk has tracks from 0 to 179. Currently the head is at track 40. The R/W requests for tracks are in the following order- 80, 102, 26, 160, 35, 10, 135. What is the total head movement when SSTF algorithm is used?

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