Answer:
(approximately 400 J)
It seems like the question is not complete, but I will asume the volume is changing from 1000 to 3000 cm3. under constant presure(2 atm).
Step-by-step explanation:
So, this is called "Isobaric process" because the presure is not changing while the volume does.
So, you just have to use the ecuation at the image.
P(V2-V1)
=2 atm (3000-1000)cm3
=4 atm . L = 405,26 J = (approximately 400 J)