Telephone expenditures. Table 15 lists average annual telephone expenditures (in dol...

Telephone expenditures. Table 15 lists average annual telephone expenditures (in dollars) per consumer unit on residential phone service and cellular phone service, and the figure contains a scatter plot and regression line for each data Set

(A) Interpret the slope of each model.

(B) Predict (to the nearest dollar) the average annual residential and cellular expenditures in 2015.

(C) Would the linear regression models give reasonable predictions for the year 2025? Explain.