Can u explain this in ur own words?
by 1987 it became clear that a great deal of pollution was coming from nonpoint sources. it was estimated that over 50 percent of the nation's remaining water pollution problems was coming from sources that are not easily identified, such as runoff from agricultural lands, construction sites, urban areas, and even forests.

Although alice walker published a number of essays, poetry collections, and stories during the 1970s, her third novel, the color purple, ) which was published in 1982, brought her the widest acclaim in that it won both the national book award as well as the pulitzer prize (b) published in 1982, bringing her the widest acclaim by winning both the national book award and the pulitzer prize (c) published in 1982, brought her the widest acclaim, winning both the national book award and the pulitzer prize (d) was published in 1982 and which, winning both the national book award and the pulitzer prize, brought her the widest acclaim (e) was published in 1982, winning both the national book award as well as the pulitzer prize, and bringing her the widest acclaim