Using the phosphorus data from the table, calculate the percentage of each phosphorus source that enters the Mississippi from the city of St. Paul.

Answer/Explanation:
% of each Nitrogen source = amount of Nitrogen from each source/total amount if Nitrogen × 100
% of Nitrogen from atmospheric deposition:
[tex] \frac{1,300}{7,400}*100 = \frac{130,000}{7,400} = 17.57 [/tex]
Approximately 18%
% of Nitrogen from household pet waste:
[tex] \frac{2,100}{7,400}*100 = \frac{210,000}{7,400} = 28.38 [/tex]
Approximately 28%
% of Nitrogen from residential fertilizer:
[tex] \frac{3,800}{7,400}*100 = \frac{380,000}{7,400} = 51.35 [/tex]
Approximately 51%
% of Nitrogen from weathering:
0%
% of Nitrogen from county compost:
[tex] \frac{200}{7,400}*100 = \frac{20,000}{7,400} = 2.70 [/tex]
Approximately 3%