Exercises 16.45 and 16.47 used the example from How It Works 15.2 on the relation between age and how much people study.

a. Construct a graph that includes both the scatterplot for these data and the regression line as determined in Exercise 16.47. Draw vertical lines to connect each dot on the scatterplot with the regression line.

b. Construct a second graph that includes both the scatterplot and a line for the mean for hours studied, 16.2. The line will be a horizontal line beginning at 16.2 on the y-axis. Draw vertical lines to connect each dot on the scatterplot with the regression line.

c. Part (a) is a depiction of the error if we use the regression equation to predict hours studied. Part (b) is a depiction of the error if we use the mean to predict hours studied (i.e., if we predict that everyone has the mean of 16.2 on hours studied per week). Which one appears to have less error? Briefly explain why the error is less in one situation.