Two surgical procedures are widely used to treat a certain type of cancer.To compare the success rates of the two procedures, random samples of the two types of surgical patients were obtained and the numbers of patients who showed recurrence (happened again) of the disease after a 1-year period were recorded.The researcher is wondering if there is sufficient evidence to conclude that procedure A is better than procedure B.Assume all assumptions and checks have been met and verified.

Pick the most appropriate answer below concerning the formulation of the null and alternative hypotheses for the test.

H : PA - PB = 0 H. : PA - PB = 0 a) b) H : PA - PB >0 H : PA - PB