The Centers for Disease Control and Prevention Office on Smoking and Health (OSH) is the lead federal agency responsible for comprehensive tobacco prevention and control. OSH was established in 1965 to reduce the death and disease caused by tobacco use and exposure to second-hand smoke. One of the many responsibilities of the OSH is to collect data on tobacco use. The following data show the percentage of adults in the United States who were users of tobacco from 2001 through 2011 (http://www.cdc.gov /tobacco/data_statistics/tables/trends/cig_smoking/index.htm):

Year__________________________Percentage of Adults Who Smoke
2001......................................................         22.8
2002......................................................         22.5
2003......................................................         21.6
2004......................................................         20.9
2005......................................................         20.9
2006......................................................         20.8
2007......................................................         19.8
2008......................................................         20.6
2009......................................................         20.6
2010......................................................         19.3
2011......................................................        18.9
a. Construct a time series plot. What type of pattern exists in the data?
b. U se simple linear regression to find the parameters for the line that minimizes MSE for this time series.
c. O ne of OSH’s Healthy People 2020 Goals is to cut the percentage of adults in the United States who were users of tobacco to 12% or less by the year 2020. Does your regression model from part (b) suggest that the OSH is on target to meet this goal? If not, use your model from part (b) to estimate the year in which the OSH will achieve this goal.