80 College 70 60 High School 0 Grade School 20 10 1949 1954 1959 1965 Figure 12.2 Respondents in national surveys stating belief that man will reach the moon, by education and year.Source:From P.J.Tichenor,G.A.Donohue,and C.N.Olien,"Mass Media Flow and Differential Growth in Knowledge,"Public Opinion Quarterly 34(1970):166.Copyright 1970 by Columbia University Press.Reprinted by permission of the University of Chicago Press. 2.At a given time,there should be a higher correlation between acquisition of knowledge and education for topics highly publicized in the media than for topics less highly publicized