Nitric oxide (NO) is emitted at 150 g/s from a stack with a physical height of 90 m. The wind speed is 4.8 m/s on a slightly sunny morning and plume rise is 20 m. (a) Calculate the ground-level centerline concentration 2.0 km downwind from the stack. (b) Calculate the concentration at 100 m off the centerline at the same x distance.