2. In 1970, the total phosphorus load to Lake Erie was 18,150 metric tons/year (1 metric ton = 1000 kg). The surface area, volume, and outflow rate from Lake Erie are given as 2.5 x 1010 m, 4.68 x 1011 m, and 1.82 x 1011 m/year, respectively. The total phosphorus is being removed by settling at a rate of 16 m/year. Assume the lake is well mixed. a. Calculate the steady state concentration of phosphorus in the lake. b. Based upon your result, is Lake Erie eutrophic?