A researcher is interested in examining the cholesterol levels of heart-attack patients. Cholesterol levels are measured for 28 heart-attack patients (2 days after their attacks) and 30 other hospital patients who did not have a heart attack. The researcher believes that cholesterol levels will be higher for the heart-attack patients. Random samples from each group provide the following results: Heart-Attack Patients Non-Heart-Attack Patients Sample Size 28 30 Mean Cholesterol (mg/DL) 213.9 193.1 Standard Deviation of Cholesterol (mg/DL) 47.7 22.3 Assume that the cholesterol levels for both populations are normally distributed and that the population standard deviations are equal. Using a 5% significance level, can the researcher conclude that the mean cholesterol level of heart-attack patients is greater than the mean cholesterol level of non-heart-attack patients? Formulate and test the appropriate hypotheses. State and explain your conclusion within the context of the question. Use the critical value approach