Answer:
The internal energy is decreased by 9.3 *10⁸ J.
Explanation:
Law of thermodynamics:
The change in internal energy (ΔU) is equal to the difference of net heat transfer (Q) occurring in the system and the net work (W) done by the system or on the system.
ΔU = Q - W
Q = -7.50 * 10⁸ J and W = 1.8 *10⁸ J
ΔU = -7.50 *10⁸ - 1.8 * 10⁸
= (-7.50 - 1.8) * 10⁸
= - 9.3 *10⁸ J