If work done by gas is asked then
${W}=\frac{\mathrm{nR} \Delta \mathrm{T}}{1-\mathrm{x}}$
Here x $=\frac{3}{2}$
$ W =\frac{\mathrm{P}_2 \mathrm{~V}_2-\mathrm{P}_1 \mathrm{~V}_1}{-\frac{1}{2}}$
$=2\left(\mathrm{P}_1 \mathrm{~V}_1-\mathrm{P}_2 \mathrm{~V}_2\right) \ldots . \text { Option (1) is correct }$
If work done by external is asked then
$\mathrm{W}=-2\left(\mathrm{P}_1 \mathrm{~V}_1-\mathrm{P}_2 \mathrm{~V}_2\right) \ldots \ldots$ Option $(2)$ is correct
