code class$=$"asciimath"$>$Problem #$11$ If R$=6\mathrm{.}0$k$\backslash$Omega $,$C$=5\mathrm{.}0$mF$,\backslash$epsi $=12\mathrm{.}0$V$,$Q$=30$mC$,$ and I$=4\mathrm{.}0$mA$,$ what is the potential difference V$\_($b$)-$V$\_($a$)?$ a$.-12\mathrm{.}0$ V b$.+18\mathrm{.}0$ V c$.-30$ V d$.+42$ V e$.-6\mathrm{.}0$ V