Complaints about rising prescription drug prices caused the U.S. Congress to consider laws that would force pharmaceutical firms to offer prescription discounts to senior citizens without drug benefits. The House Government Reform Committee provided data on the prescription cost for some of the most widely used drugs. Assume the following data show a sample of the prescription cost in dollars for Zocor, a drug used to lower cholesterol.
110 112 115 99 100 98 104 126
a. Provide a point estimate of the variance of prescription cost.
b. Construct a 95% confidence interval for the variance of prescription cost.
c. Test the null hypothesis that population variance is $100 dollars against an alternative that it is greater than $100. Assume = 0.05.