Find flux related to shaded face BCFG

$\begin{array}{l}{\mathrm{\varphi }}_{\text{BCFG }}={\mathrm{\varphi }}_{\text{due }}\text{ to }\mathrm{q}+{\mathrm{\varphi }}_{\text{due }}\text{ to }3\mathrm{q}+{\mathrm{\varphi }}_{\text{due }}\\ \text{ to }2\mathrm{q}\\ {\mathrm{\varphi }}_{\text{due to }\mathrm{q}}=\frac{\mathrm{q}}{24{\mathrm{\epsilon }}_0}\\ {\mathrm{\varphi }}_{\text{due }}\text{ to }3\mathrm{q}=\frac{3\mathrm{q}}{24{\mathrm{e}}_0}\\ {\mathrm{\varphi }}_{\text{due to }2\mathrm{q}}=0\\ {\mathrm{\varphi }}_{\text{BCGF }}=\frac{\mathrm{q}}{24{\mathrm{\epsilon }}_0}+\frac{3\mathrm{q}}{24{\mathrm{\epsilon }}_0}+0=\frac{4\mathrm{q}}{24{\mathrm{\epsilon }}_0}=\frac{\mathrm{q}}{6{\mathrm{\epsilon }}_0}\end{array}$