Glycerin (c_p = 2400 J/kg·K) at 20°C and 0.5 kg/s is to be heated by ethylene glycol (c_p = 2500 J/kg·K) at 60°C in a thin-walled double-pipe parallel-flow heat exchanger. The temperature difference between the two fluids is 15°C at the outlet of the heat exchanger. If the overall heat transfer coefficient is 240 W/m²·K and the heat transfer surface area is 3.2 m², determine

(a) the rate of heat transfer,

(b) The outlet temperature of the glycerin,

(c) The mass flow rate of the ethylene glycol.