The net change in internal energy of the gas can be calculated using the first law of thermodynamics:
ΔU = Q - W
where ΔU is the change in internal energy, Q is the amount of heat transferred to the gas, and W is the work done on the gas.
In this case, Q = 1080 J (heat transferred to the gas) and W = -400 J (negative sign indicating work done on the gas).
Plugging in these values:
ΔU = 1080 J - (-400 J)
= 1080 J + 400 J
= 1480 J
Therefore, the net total change in internal energy of the gas in the box is 1480 J.