A chimney with a design stack height of 300 m is emitting sulphur dioxide at a rate of 600 g/s on a sunny day in June (strong incoming solar radiation with unstable air conditions) with moderate wind speed (wind speed is 5 m/s) the stack altitude. Estimate the concentration of sulphur dioxide (in g/m) downwind for the following situations: (1000, 0, 0, 300); (1000, 50, 0, 300); (1000, 50, 20, 300)