Answer all Two questions

SECTION $-$B

$220M=40M$

$($a$)$ Consider a double$-$side$-$platter disk with the following parameters: Rotation speed: $755$ rpm; Number of Tracks on one side of platter: $2550$; Number of sectors per track: $128$; See time: four ms for every hundred tracks traversed. Let the disk receive a request to access random sector on a random track and assume the disk head starts at track $0.$

$8M$

$($i$)$ Draw the layout structure of Disk.

$($ii$)$ Find the capacity of the disk.

$($iii$)$ Determine the average seek time?

$($iv$)$ Determine the average rotational latency?

$($b$)$ Illustrate the different RAID levels, and how do they differ from one another? $[6$M$]$

$($c$)$ Calculate and compare the read and write performance of a RAID$-4$ and RAID$-5$ system suppose if we have $4$ disks, each with a capacity of $2GB,$ data block size of $512MB,$ par block size of $256MB$ and the write penalty is $4.[6$M$]$