General: Seat Belt Use Because of driver education programs and stricter laws, seat belt...

General: Seat Belt Use Because of driver education programs and stricter laws, seat belt use has increased steadily over recent decades. The following table gives the percentage of automobile occupants using seat belts in selected years.

a. Number the data columns with x-values 1–4 and use linear regression to fit a line to the data. State the regression formula. [Hint: See Example 9.]

b. Interpret the slope of the line. From your answer, what is the yearly increase?

c. Use the regression line to predict seat belt use in 2017. [Hint: What (decimal) x-value corresponds to 2017?]

d. Would it make sense to use the regression line to predict seat belt use in 2025? What percentage would you get?