Molar Heat Capacities: the Temperature of an Ideal Gas in a Sealed

Molar heat capacities: The temperature of an ideal gas in a sealed 0.40 container is reduced from 400 K to The final pressure of the gas is The molar heat capacity at constant volume of the gas is 28.0 J/mol · K. The work done by the gas is closest to

A) 0.00 kJ.
B) -19 kJ.
C) -25 kJ.
D) 19 kJ.
E) 25 kJ.