How do I start this problem please?

A closed cylinder contains 40 ml of gas at 800 kPa. The gas expands to a volume of

400 ml according to the relationship pV1.1 = constant. If the heat transfer from the gas to the

surroundings is 300 J, calculate the change in internal energy of the gas during the expansion

process.

Do I use W = P(V2-V1)^1.1 ?

Thanks

Calculate P2 using PV^1.1 = C relation i.e. P1*V1^1.1 = P2*V2^1.1

therefore P2/P1 = (V1/V2)^1.1

Once you know P2, the work done in polytropic process in closed system is given by,

W= (P1V1-P2V2)/(n-1)

n=cp/cv in our case n=1.1 given

then internal energy is calculated using first law.