The report ?Daily Cigarette Use: Indicators on Children and Youth? (Child Trends Data Bank, childtrends.org/wp-content/uploads/2012/11/03 _Smoking_new.pdf, retrieved April 17, 2017) included the accompanying data on the percentage of students who report smoking cigarettes daily, for students in grades 8, 10, and 12.?

a. Construct a time series plot for students in grade 12, and comment on any trend over time.?

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

c. Write a paragraph based on the plot from Part (b). Discuss the similarities and differences for the three grade levels.