Answer
$\phi=51.1\frac{N.m^2}{C}$
Work Step by Step
We know that:
$\rho=\frac{q}{V}$
This can be rearranged as:
$q=\rho V$
$q=4.5\times 10^{-10}C$
Now according to Gauss's law
$\phi=\frac{q}{\epsilon_{\circ}}$
We plug in the known values to obtain:
$\phi=\frac{4.5\times 10^{-10}}{8.85\times 10^{-12}}=51.1\frac{N.m^2}{C}$
