Question $3$: $(1\mathrm{.}25$pt$)$mass of $3\mathrm{.}0$kg is subject to a force F$($x$)=8\mathrm{.}0$N$-(4\mathrm{.}0$Nm$)$x$.$The potential energy of the mass is zero at x$=0.$What is the potential energy of the mass at x$=2\mathrm{.}0$m $?$ A$)4\mathrm{.}0$J B$)0\mathrm{.}0$J C$)8\mathrm{.}0$J D$)-4\mathrm{.}0$J E$)-8\mathrm{.}0$J