A container holds gas at a constant pressure of 5100 Pa. A machine then expands the walls of the container from an initial volume of 150 m3 to some unknown final volume. If the machine released 290 kJ of heat into the gas, and the change in internal energy is 120 kJ, what is the final volume

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.