A study was conducted to look at blood cholesterol levels in smokers compared to ex-smokers. In this particular study a person was categorized as being a "smoker" if they had smoked for at least 25 years, and as an "ex-smoker" if they had smoked for less than 5 years, and was no longer smoking. 1. Below you see two histograms for the blood cholesterol levels for smokers and ex-smokers respectively. Frequency 10 Smoker 100 150 200 250 300 Smoker Ex-smoker 350 400 100 150 200 250 300 350 400 cholesterol 2. Consider the two histograms. Do you believe it is reasonable to assume that the data in each group is approximately normally distributed? 3. Formulate the statistical null hypothesis and the alternative hypothesis 6. What kind of statistical test would you propose to test this hypothesis? Please explain your answer. 7. How many degrees of freedom would this test have?