7. (pts) Circle those phrases below that make the statement True. Plotting of residuals cannot be used to determine if : a. a relevant independent variable has been left out of the regression. b. a quadratic rather than a linear relationship would be more appropriate. c. outliers can be identified in the data. d. the residual sum of squares has been minimized. 8. (5 pts) Given the following H (hat ) matrix with diagonal elements . . 34 where hi. she for ity - 45 . 24 . 49 How many observations were included in the analysis. Explain your c