The work done in increasing the size of a soap film from 10 cm× 6 cm to 10 cm × 11 cm is 3 ×10^-4 joule. The surface tension of the film is

• A

  $1.5\times {10}^{-2}\mathrm{N}/\mathrm{m}$

• B

  $3.0\times {10}^{-2}\mathrm{N}/\mathrm{m}$

• C

  $6.0\times {10}^{-2}\mathrm{N}/\mathrm{m}$

• D

  $11.0\times {10}^{-2}\mathrm{N}/\mathrm{m}$