In a survey of 552 U.S. businesses, 400 of such companies indicated that they monitor employees' web site visits. For purposes of this exercise, suppose that it is reasonable to regard this sample as representative of businesses in the United States.
a) Is there sufficient evidence to conclude that more than 75% of U.S. businesses monitor employees' web site visits? Test the appropriate hypotheses using a significance level of 0.01.
b) Is there sufficient evidence to conclude that a majority of U.S. businesses monitor employees' web site visits? Test the appropriate hypotheses using a significance level of 0.01.