A large cooling tower fan has a diameter of 10 m and is a tube axial type. It provides 600 m3/s at a total pressure rise of 500 Pa with an air weight density of 10.0 N/m3. a. Estimate the sound power level, Lw, of the fan using the modified Graham method and the tip speed method. b. Calculate the sound pressure level, Lp, at a distance of 50 m from the fan inlet (assume free field propagation).