$16\mathrm{.}8$ Give the common name or CA$/$IUPAC name,

whichever is appropriate, for each of the following compounds:

$($a$)C{H}_{3}C{H}_{2}C{H}_{2}C{H}_{2}NHCH(C{H}_3{)}_2$

$($b$)$

$($c$)$

$($d$)$