12.69 Acid precipitation studies in southeastern Arizona involved sampling rain from two sites

(Bisbee and the Tucson Research Ranch of the National Audubon Society) and sampling air from smelter plumes. The data for five elements, in terms of their ratios to copper, are given in the Table 12.19. One objective of the study is to see if the plume samples differ from the rain samples at the oilier sites. What can you say about this aspect of the study?