A watershed consisting of heavily wooded and grassland area drains into a culvert under a roadway. The total area of the watershed is 310 acres. The 10-year runoff coefficient has been determined to be 0.36. The 10-year and 100-year rainfall intensities have been determined to be 1.2 in/hr and 1.94 in/hr, respectively. Determine de 100-year runoff coefficient and the 10-year and 100-year design discharges to be conveyed by the culvert under the roadway.

At steady state, air at 200 kpa, 325 k, and mass flow rate of 0.5 kg/s enters an insulated duct having differing inlet and exit cross-sectional areas. the inlet cross-sectional area is 6 cm2. at the duct exit, the pressure of the air is 100 kpa and the velocity is 250 m/s. neglecting potential energy effects and modeling air as an 1.008 kj/kg k, determine ideal gas with constant cp = (a) the velocity of the air at the inlet, in m/s. (b) the temperature of the air at the exit, in k. (c) the exit cross-sectional area, in cm2