An acidic solution of dichromate is electrolyzed for 8 minutes using 2 A current. As per the following equation

${\mathrm{Cr}}_2{\mathrm{O}}_7^2+14{\mathrm{H}}^{+}+6{\mathrm{e}}^{-}\to 2{\mathrm{Cr}}^{3+}+7{\mathrm{H}}_2\mathrm{O}$
The amount of ${\mathrm{Cr}}^{3+}$. obtained was $0.104\mathrm{g}$. The efficiency of the process $(\mathrm{in}\%)$ is (Take : $\mathrm{F}=960000\mathrm{C}$, At. mass of chromium $=52$)