Two pounds of carbon dioxide (co2) as an ideal gas executes a carnot power cycle while operating between thermal reservoirs at 500 and 100of. the pressures at the initial and final states of the isothermal expansion are 400 and 200 lbf/in2, respectively. the specific heat ratio is k = 1.24. determine the thermal efficiency, the work for the isothermal expansion, in btu, and the work for the adiabatic expansion, in btu.