William Tindall (A-34) performed a retrospective study of the records of patients receiving care for hypercholesterolemia. The following table gives measurements of total cholesterol for patients before and 6 weeks after taking a statin drug. Is there sufficient evidence at the a ¼ :01 level of significance for us to conclude that the drug would result in reduction in total cholesterol in a population of similar hypercholesterolemia patients?