Consider 5 kg of air initially at 101.3 kPa and 38 C. Heat is transferred to the air until the temperature reaches 260 C. Determine the change in internal energy, the change in enthalpy, the heat transfer, and the work done for (a) a constant-volume process and (b) a constant-pressure process. Use SI units. Show pv and tv graphs. Are the systems closed and are they rigid?