A gas undergoes two successive processes:
Process I: absorbs 200J of heat and does 250J of work on the surroundings.
Process II: releases 150J of heat while 100J of work is done on the gas.
Determine the net change in internal energy ΔUnet for the gas after both processes.
a) +100J
b) −100J
c) −350J
d) +200J