Answer:
The time required to seek using First come,first served algorithm is 876 milliseconds.
The time required to seek using Shortest Seek Time First algorithm is 360 milliseconds.
The time required to seek using LOOK (initialing moving upwards) algorithm is 348 milliseconds.
Explanation:
Part a,b : First-come, first-served:
The order of the cylinders is as 10, 22, 20, 2, 40, 6, 38
10 + 12 + 2 + 18 + 38 + 34 + 32 = 146 cylinders = 876 milliseconds.
ii) Shortest Seek Time First:
The order of the cylinders is as 20, 22, 10, 6, 2, 39, 40
0 + 2 + 12 + 4 + 4 + 36 + 2 = 60 cylinders = 360 milliseconds.
iii) LOOK (initialing moving upwards):
The order of the cylinders is as 20, 22, 38, 40, 10, 6, 2
0 + 2 + 16 + 2 + 30 + 4 + 4 = 58 cylinders = 348 milliseconds.