The surface tension of a soap solution is 3.5 × 10^-2 N / m. The work required to increase the radius of a soap bubble from 1 cm to 2 cm is α × 10^-6…

The surface tension of a soap solution is $\displaystyle 3.5 \times 10^{-2} \mathrm{~N} / \mathrm{m}$. The work required to increase the radius of a soap bubble from $\displaystyle 1$ cm to $\displaystyle 2$ cm is $\displaystyle \alpha \times 10^{-6} \mathrm{~J}$. The value of $\displaystyle \alpha$ is $\displaystyle \_\_\_\_$. $\displaystyle (\pi=22 / 7)$