Seek time
Seek time - the time taken for a disk drive to locate the area on the disk where the data to be read is stored.
Rotational Latency
A rotational delay is the amount of time between information requests and how long it takes the hard drive to move to the sector where the requested data is located.
FCFS
Total time is estimated by total arm motion
=(100-23)+(89-23)+(132-89) +(132-42) +(189-42) =77+66+43+90+147
=423
SJTF
Total time is estimated by total arm motion
=(100-89)+(132-89)+(189-132) +(189-42) +(42-23) =11+43+57+147+19
=277
