Test Statistics Identify the test statistics that should be used for testing the following claims.

a. The mean of the differences between platelet counts of husbands and platelet counts of their wives is equal to 0.

b. The mean platelet count of adult Californians is equal to the mean platelet count of adult Texans.

c. The proportion of men with diabetes is equal to the proportion of women with diabetes.

d. The variation among pulse rates of women is equal to the variation among pulse rates of men.