At a large university, an SRS of 25 male faculty members included 10 that felt that the university was supportive of female and minority faculty. An SRS of 20 female faculty found five that felt the university was supportive of female and minority faculty. Let p1 and p2 represent the proportion of all male and female faculty, respectively, who felt that the university was supportive of female and minority faculty. A 95% plus four confidence interval for p1 – p2 is
a. 0.15 ± 0.270.
b. 0.135 ± 0.263.
c. 0.135 ± 0.270.
d. 0.15 ± 0.263