A rigid, sealed steel tank containing an ideal gas is initially at a surface atmospheric temperature of \(T_1 = 300\text{ K}\) and pressure \(P_0 = 1.0 \times 10^5\text{ Pa}\). The tank is lowered to a deep ocean depth where the surrounding water temperature is \(T_2 = 270\text{ K}\). Which of the following claims about the gas inside the tank after it reaches thermal equilibrium with the ocean water is correct, and provides the correct justification?