Refer to North Carolina Birth Registry Data NCBIRTH800 with 800 observations (see Large Data Exercise 1 in Chapter 2). Calculate 95 percent confidence intervals for the following:

(a) the percentage of male children

(b) the mean age of a mother giving birth

(c) the mean weight gained during pregnancy

(d) the percentage of mothers admitting to smoking during pregnancy

(e) the difference in the average weight gained between smoking and nonsmoking mothers

(f) the difference in the average birth weight in grams between married and nonmarried mothers

(g) the difference in the percentage of low birth weight babies between married and nonmarried mothers