Consider the following sequence of disk track requests: $120,50,11,22,27,76,166,52$ and $140.$ Assume that the disk head is initially positioned over track $50$ and is moving in the direction of increasing track number.

a$)$How many tracks will have to be traversed $($total seek length$)$ and what is the average number of tracks to be traversed $($average seek length$)$ if we use the SSTF scheduling policy?

b$)$Repeat $($a$),$ this time using the SCAN scheduling policy.

c$)$Repeat $($a$),$ this time using the C$-$SCAN scheduling policy.