$($a$)$

Give one simple real$-$life example of a device where it is a good idea to use program$-$controlled I$/$O$.$

$($b$)$

Give one simple real$-$life example of another device where it is a good idea to use interrupt$-$based I$/$O$.$

$($c$)$

Explain the advantage of interrupt$-$based I$/$O over program$-$controlled I$/$O in terms of the workload of the CPU.