Thermal Kinetic Physics Question involving PV diagram

[KaseyKC]

Homework Statement

I'm stuck on question A4 that is linked below. University won't provide me with any solutions. I have a TKP resit exam next month.

Homework Equations

dU=dQ-PdV

The Attempt at a Solution

Internal energy is equal to heat flow plus the work done. Work done is 0 because it's isochoric. So Internal energy is equal to the heat flow right? 20J.

 

[TSny]

Hello, KaseyKC. Welcome to PF!

Be careful with how you word your answer. The heat added to the system plus the work done on the system equals the change in internal energy of the system.

Otherwise, your answer looks good.