$4\mathrm{.}48$ In an electric field E$520$r sin u ar $110$r cos u au V$/$m$,$ calculate the energy expendedin transferring a $10$ nC charge$($a$)$ From A $15,30\backslash$deg $,0\backslash$deg $2$ to B $15,90\backslash$deg $,0\backslash$deg $2($b$)$ From A to C $110,30\backslash$deg $,0\backslash$deg $2($c$)$ From A to D $15,30\backslash$deg $,60\backslash$deg $2($d$)$ From A to E $110,90\backslash$deg $,60\backslash$deg $2$