A balloon filled with 27.3 mol helium has a volume of 612. L at 0.0°C and 1.00 atm pressure. The temperature of the balloon is increased to 33.0°C as it expands to a volume of 686. L, the pressure remaining constant. Calculate q, w, and ΔE for the helium in the balloon. (The molar heat capacity for helium gas is 20.8 J/°C·mol.)