It is proposed that the stationary diesel exhaust gases (CO2) be used for heating air by the use of a double-pipe heat exchanger. CO2 flows through the annulus. From the measurements of the velocity, it is calculated that the mass flow rate of gases from the engine is 100 kg/h. The exhaust gas temperature is 600 K. The air is available at 20°C and it will be heated to 80°C at a mass flow rate of 90 kg/h. One standard tube size of 4 × 3 in. (The outer pipe has a nominal diameter of 4 in. and the inner pipe has a nominal diameter of 3 in.) in a double-pipe exchanger (hairpin) of 2 m length (copper tubes) will be used. a. Calculate the frictional pressure drop in the inner tube. b. Calculate the pressure drop (Pa) in the annulus. c. Calculate the pumping power for both streams. (Assuming the average temperature of CO2 at 500 K and the following properties: p = 1.0732 kg/m³, c₂ = 1,013 J/kg · K, k = 0.03352 W/m K, Pr = 0.702, v = 21.67 × 10-6 m²/s. For air: C = 1,007 J/kg . K.) .