The gas inside a spherical bubble expands uniformly and slowly so that its radius increases from $R$ to $2R$. The atmospheric pressure is $P_0$ and surface tension is $s$. The work done by the gas in the process is

• Correct answer
  A

  $\frac{28\mathrm{\pi }{\mathrm{R}}^3{\mathrm{P}}_0}{3}+24\mathrm{\pi }\mathrm{s}{\mathrm{R}}^2$
• B

  $\frac{25\mathrm{\pi }{\mathrm{R}}^3{\mathrm{P}}_0}{3}+24\mathrm{\pi }\mathrm{s}{\mathrm{R}}^2$
• C

  $\frac{25\mathrm{\pi }{\mathrm{R}}^3{\mathrm{P}}_0}{3}+\frac{23\mathrm{\pi }\mathrm{s}{\mathrm{R}}^2}{2}$
• D

  $23\mathrm{\pi }\mathrm{s}{\mathrm{R}}^2$

Hence, the correct answer is option: 'A'.