(N/A) $(i)$ If the total charge contained in a closed surface is zero,then the net electric flux through that closed surface is zero.
$(ii)$ Gauss's law is valid for any closed surface,regardless of its shape or size.
$(iii)$ The charges can be located anywhere inside the surface.
$(iv)$ When a surface is chosen such that some charges are inside and some are outside,the electric field on the left side of the equation $\phi = \frac{\Sigma q}{\epsilon_{0}}$ is due to all charges (both inside and outside). However,the term $\Sigma q$ on the right side represents only the total charge enclosed within the surface.
$(v)$ The surface chosen for the application of Gauss's law is called a Gaussian surface.
$(vi)$ Gauss's law is useful for simplifying the calculation of electrostatic fields when the system possesses symmetry.
$(vii)$ Gauss's law is based on the inverse square dependence of the electric field on distance.