) A diffuser takes in 2.5 kg s−1 of air at 52 ◦C and 12 bar through an inlet of 4 cm. It discharges through an outlet of 12 cm diameter at 10 bar and 152 ◦C. The diffuser is heated. Determine inlet and outlet velocities, the change in enthalpy that occurs, and the heat gain. Assume air is an ideal gas. [155 m s−1 , 27.0 m s−1 , −11.5 kJ kg−1 ]