The data set below contains spending on products$($$$)$ during a$$ three$-$month period by a sample of $15$ customers receiving incentives through a mobile loyalty program. Complete parts$($a$)$ through$($d$)$ below.

$55\mathrm{.}03$

$22\mathrm{.}83$

$67\mathrm{.}49$

$46\mathrm{.}09$

$57\mathrm{.}05$

$108\mathrm{.}42$

$50\mathrm{.}71$

$35\mathrm{.}73$

$78\mathrm{.}14$

$50\mathrm{.}58$

$63\mathrm{.}52$

$59\mathrm{.}65$

$41\mathrm{.}69$

$56\mathrm{.}35$

$53\mathrm{.}81$