A nighttime cold medicine bears a label indicating the presence of 600 mg of acetaminophen in each fluid oz of the drug. Suppose that Health Canada randomly selected 65 one-oz samples and found that the mean acetaminophen content was 589 mg, and the standard deviation was 21 mg. Using α = 0.01, test the claim of the pharmaceutical company that the population mean is equal to 600 mg. Would you buy this cold medicine?