Solution:

Specifying the total charge inside the surface is a sufficient condition for finding the electric flux \( \Phi \) through a closed surface.

According to Gauss's law:
\[
\Phi = \frac{q_{\text{enclosed}}}{\varepsilon_0}
\]

The flux depends only on the enclosed charge \( q_{\text{enclosed}} \), regardless of the surface's shape or the charge distribution.