$1.$ When $+3\mathrm{.}0$ C of charge moves from point A to point B in an electric field, the potential energy

is decreased by $27$ J$.$ It can be concluded that point B is

$($a$)9\mathrm{.}0$ V lower in potential than point A$.$

$($b$)9\mathrm{.}0$ V higher in potential than point A$.$

$($c$)81$ V higher in potential than point A$.$

$($d$)81$ V lower in potential than point A$.$