Air at 1 atm and 285 k enters a 2-m-long rectangular duct with cross section 75 mmx150 mm. the duct is maintained at a constant surface temperature of 400 k, and the air mass flow rate is 0.10 kg/s. determine the heat transfer rate from the duct to the air and the air outlet temperature.

At steady state, air enters an insulated duct of varying cross-sectional area (similar to a nozzle or diffuser) at 200 kpa, 52°c with a mass flow rate of 0.5 kg/s. at the duct exit, the pressure of the air is 100 kpa, the velocity is 255 m/s, and the cross-sectional area is 2 x 10-3 m^2. assuming an ideal gas model, determine: a)-find the specific volume of the air at the exit, in m3/kg. b)- the temperature of the air at the exit, in k. c)-the velocity of the air at the inlet, in m/s. d)-the inlet cross-sectional area, in m^2.