Answer:
60 J of heat are released from the system: Q=-60 J
20 J of work is done on the system: W=-20 J
∆U=Q-W
∆U=-60-(-20)
∆U=-40 J
Explanation:
If the heat is released from the system, Q should be negative.
If the heat is gained by the system, Q should be positive.
If the work is done on the system, W should be negative.
If the work is done by the system, W should be positive.
