One of the important factors determining a car's fuel efficiency is its weight.This relationship is examined for 11 cars,and the association is shown in the scatterplot below. If a linear model is considered,the regression analysis is as follows: Dependent variable: MPG R-squared = 84.7% VARIABLE COEFFICIENT Intercept 47.1181 Weight -7.34614 The residuals plot is: Based upon the residuals plot,do you think that this linear model is appropriate? A)Yes,residuals show no pattern. B)Yes,residuals show a linear pattern. C)No,residuals show a curved pattern. D)No,residuals show no pattern. E)Yes,residuals show a curved pattern.

Doctors studying how the human body assimilates medication inject some patients with penicillin,and then monitor the concentration of the drug (in units/cc)in the patients' blood for seven hours.First they tried to fit a linear model.The regression analysis and residuals plot are shown.Is that estimate likely to be accurate,too low,or too high? Explain.