Refer to the study on ordering vegetarian considered in Examples 12.8-12.10.
a. Obtain the margin of error for the estimate of the difference between the proportions of men and women who sometimes order veg by taking half the length of the confidence interval found in Example 12.10 on page 567. Interpret your answer in words.
b. Obtain the margin of error for the estimate of the difference between the proportions of men and women who sometimes order veg by applying Exercise 12.132.