Q$10.$ External fragmentation is a common problem shared by both memory

management and file system management. Most file systems provide the defragmentation mechanism that moves the data blocks of files to reclaim contiguous space. On the other hand, it is not as common to see operating systems perform memory defragmentation.

$($a$)$ Aside from the shortage of contiguous space, what are the negative impacts $($s$)$ of external fragmentation on a file system?

$($b$)$ Are those impacts applicable to memory management as well? Why or why not?

$($c$)$ If we still want to carry out defragmentation on the memory, what might be the challenge$($s$)?$