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8. Three individuals, Mary, Jack and Helen, make up the total demand for donuts per month in a particular market. Mary's demand curve is 5P = 5000 - 1.25Q. Jack's demand curve for donuts is given by P = 1000 - 0.5Q,. Helen's demand curve is given by Qu = 2000 -2P. The market demand curve would be: A) Q = 400 - 0.25P B) P = 400 - 0.125Q C) P = 1000 - 0.25Q D) P= 1000 - 0.125Q E) P = 1000 - 1.25Q F) P = 1000 - 4