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The Centers for Disease Control reported the percentageof people 18 years of age and older who smoke (CDC website,December 14, 2014). Suppose that a study designed to collect newdata on smokers and nonsmokers uses a preliminary estimate of theproportion who smoke of .28.a. How large a sample should be taken to estimate the proportionof smokers in the population with a margin of error of .02 (to thenearest whole number)? Use 95% confidence.b. Assume that the study uses your sample size recommendation inpart (a) and finds 520 smokers. What is the point estimate of theproportion of smokers in the population (to 4 decimals)?c. What is the 95% confidence interval for the proportion ofsmokers in the population (to 4 decimals)?( , )