Question $2(12\mathrm{.}5$ points$)$

Two charges of $15$ pC and $-40$ pC are inside a cube with sides that are of $0\mathrm{.}40-m$ length. Determine the net electric flux through the surface of the cube.

$+1\mathrm{.}1N\frac{m^2}{C}$

$+2\mathrm{.}8N\frac{m^2}{C}$

$-0\mathrm{.}47N^{-1}\frac{m^2}{C}$

$-2\mathrm{.}8N\frac{m^2}{C}$

$-1\mathrm{.}1N\frac{m^2}{C}$