The surface tension of soap solution is $0.03 N/m$. The work done in blowing to form a soap bubble of surface area $40\;cm^2$, in Joules, is

Question

\[\begin {array} {1 1} (1)\;1.2 \times 10^{-4} & \quad (2)\;2.4 \times 10^{-4} \\ (3)\;12 \times 10^{-4} & \quad (4)\;24 \times 10^{-4} \end {array}\]