The rate of emission of SO2 from the stack of a power plant is 278.2 g/s. The effective height of the stack is 88 m. Calculate the SO2 concentration in parts per million at a parking lot located 900 m directly downwind from the stack for neutral (class D overcast), stable (class F at night) and unstable (class A, sunny August day) urban conditions. Assume a wind speed of 2 m/s and use the charts in the notes for the dispersion parameters. Calculate the concentration 200 m perpendicular to the centerline for all stability classes too.