The table on the facing page, based on a simple random sample of 33 families from a community of 600 families, gives the family size, weekly net family income, and weekly cost of medical expenditures including pharmaceuticals.

The community contains 2700 persons.

a. Estimate, and give a 95% confidence interval for, the average weekly medical expenditure per family.

b. Estimate, and give a 95% confidence interval for, the average weekly medical expenditure per person. Justify your method of estimation.

Estimate, and give a 95% confidence interval for, the average proportion of family income spent on medical expenses.

d. Estimate, and give a 95% confidence interval for, the total weekly medical expenses paid by the community.

e. Estimate, and give a 95% confidence interval for, the average proportion of family income spent on medical expenses for families whose weekly net income is less than $400. Do the same for those whose weekly net income is greater than $400.