Watch your cholesterol:A sample of 314 patients between the ages of 38 and 82 were given a combination of the drugs ezetimibe and simvastatin. They achieved a mean reduction in total cholesterol of 0.94 millimole per liter. Assume the population standard deviation is= 0.18.

a. Construct a 98% confidence interval for the mean reduction in total cholesterol in patients who take this combination of drugs.

c. Based on the confidence interval constructed in part (a), is it likely that the mean reduction in cholesterol level is less than 0.90?