Refer to the previous exercise.
a. Find the standard error of (p̂1 – p̂2) for a test of H0: p1 = p2.
b. For a two-sided test, find the test statistic and P-value, and make a decision using significance level 0.05. Interpret.
c. Suppose that actually p1 = 0.81 and p2 = 0.72. Was the decision in part b in error?
d. State the assumptions on which the methods in this exercise are based.