The surface tension of a soap solution is $2\times {10}^{-2}\mathrm{N}/\mathrm{m}.$ To blow a bubble of radius 1 cm, the work done is

• A

  $4\mathrm{\pi }\times {10}^{-6}\mathrm{J}$

• B

  $8\mathrm{\pi }\times {10}^{-6}\mathrm{J}$

• C

  $12\mathrm{\pi }\times {10}^{-6}\mathrm{J}$

• D

  $16\mathrm{\pi }\times {10}^{-6}\mathrm{J}$