Write the $SI$ unit of electric flux.

(N/A) Electric flux $\Phi_E$ is defined as the product of the electric field $E$ and the area $A$ through which it passes,given by $\Phi_E = E \cdot A$.
The $SI$ unit of electric field $E$ is $\text{newton per coulomb}$ $(N/C)$ or $\text{volt per meter}$ $(V/m)$.
The $SI$ unit of area $A$ is $\text{square meter}$ $(m^2)$.
Therefore,the $SI$ unit of electric flux is $(N/C) \cdot m^2 = N \cdot m^2/C$ or $(V/m) \cdot m^2 = V \cdot m$.
Thus,the $SI$ unit of electric flux is $N \cdot m^2 \cdot C^{-1}$ or $V \cdot m$.