$3-$ If we integrate Both sides orev open Surface $S^{\text{'}}$ we obtien.

$\frac{?}{\text{b}\text{a}\text{r}}(grad)\frac{}{b}ar(E)=0$Longrightarrowo${\displaystyle \underset{1}{\overset{\phantom{}}{}}}*dl=0,$ prove the two equation

$\frac{?}{\text{b}\text{a}\text{r}}(grad)\frac{}{b}ar(E)=0$Longrightarrowo${\displaystyle \underset{1}{\overset{\phantom{}}{}}}E*dl=$ o $>$prove these teo rqualion