An experimental cryogenic chamber on board a high-altitude research balloon contains 4.5 mol of helium gas. Helium behaves as an ideal monatomic gas under these conditions. If the temperature of the gas in the chamber is maintained at −25 ∘C-25\text{ }^\circ\text{C}−25 ∘C, what is the total internal energy of the helium gas?
5.13×10−21 J5.13 \times 10^{-21}\text{ J}5.13×10−21 J
1.40×103 J1.40 \times 10^3\text{ J}1.40×103 J
1.39×104 J1.39 \times 10^4\text{ J}1.39×104 J
9.28×103 J9.28 \times 10^3\text{ J}9.28×103 J
