96 For each of the following combinations of a and degrees of freedom (df), find the values of x2 a/2 and x2

(1-a/2) that would be used to form a confidence interval for s2 .

a. a = .05, df = 7

b. a = .10, df = 16

c. a = .01, df = 20

d. a = .05, df = 20