A consumer advocacy group is concerned about the variability in the cost of prescription medication. The group surveys eight local pharmacies and obtains the following prices for a particular brand of medication:
$25.50 32.00 33.50 28.75 29.50 35.00 27.00 29.00
a. Calculate the point estimate for the population variance.
b. The group assumes that the prices represent a random sample drawn from a normally distributed population. Construct the 90% interval estimate for the population variance.
c. The group decides to begin a lobbying effort on its members' behalf if the variance in the price does not equal 4. What should the group do?