3.44 The report “Trends in Higher Education’ (www.collegeboard

.com) gave the accompanying data on smoking rates for people age 25 and older by education level.

Percent Who Smoke Year Not a High School Graduate High School Graduate but No College Some College Bachelor's Degree or Higher 1960 44 46 48 44 1965 44 45 47 41 1970 42 44 45 37 Percent Who Smoke Year Not a High School Graduate High School Graduate but No College Some College Bachelor's Degree or Higher 1975 41 42 43 33 1980 38 40 39 28 1985 36 37 36 23 1990 34 34 32 19 1995 32 31 29 16 2000 30 28 26 14 2005 29 27 21 10

a. Construct a time series plot for people who did not graduate from high school and comment on any trend over time.

b. Construct a time series plot that shows trend over time for each of the four education levels. Graph each of the four time series on the same set of axes, using different colors to distinguish the different education levels. Either label the time series in the plot or include a legend to indicate which time series corresponds to which education level.

c. Write a paragraph about your plot from Part (b).
Discuss the similarities and differences for the four different education levels.