A sample of gas expands from an initial pressure and volume of 10Pa and 1.0m³ to a final volume of 2.0m³, the pressure and volume are related by the equation $\mathrm{P}={\mathrm{aV}}^2$  , where $\mathrm{a}=10\mathrm{N}/{\mathrm{m}}^8$ . Find the work done by the gas during the expansion.