$$ \begin{aligned} & \mathrm{I}_{\text {avg }}=\frac{1}{2} \varepsilon_0 \mathrm{E}_0^2 \mathrm{C} \\ & \frac{1.25}{100} \times \frac{1000}{4 \pi(2)^2}=\frac{1}{2} \times 8.85 \times 10^{-12} \times 3 \times 10^8 \times \mathrm{E}_0^2 \\ & \mathrm{E}_0^2=187.4 \\ & \therefore \mathrm{E}_0=13.689 \mathrm{~V} / \mathrm{m} \\ & =136.89 \times 10^{-1} \mathrm{~V} / \mathrm{m} \\ & \therefore \mathrm{x}=136.89 \end{aligned} $$ Rounding off to nearest integer $$ x=137 $$