A $4F$ capacitor is charged to a potential difference of $100$ V $.$

The electric energy $U_E$ stored in the capacitor is

$U_E=2{10}^{-2}J.$

$U_E=2{10}^{-10}J.$

$U_E=2{10}^{-6}J.$

$U_E=2{10}^{-8}J.$

$U_E=2{10}^{-4}J.$