Physics Homework Question: Constant-volume processes?

A rigid aluminum cylinder contains some nitrogen gas. The cylinder has m 0.935 kg, and it is in thermal equilibrium with the gas. After 2.41�104 J of heat are transferred to the system consisting of the cylinder and the gas, their temperature increases 27.9 K, and they are again in thermal equilibrium. What is the change in internal energy of the gas? (The specific heat of aluminum is 897 J/kg�K.) Answer must be in Joules