Answer the questions using complete sentences. a. What is an influential point? How should influential points be treated when doing a regression analysis? b. What is the coefficient of determination and what does it measure? c. What is extrapolation? Should extrapolation ever be used? a. Choose the correct answer below. O A. An influential point is a point that does not fit the trend. If the data have one or more influential points, perform the regression analysis with and without these points and comment on the differences. O B. An influential point is an outlier whose presence or absence has a large effect on the regression analysis. If the data have one the differences. more influential points, perform the regression analysis with and without these points and comment on OC. An influential point is a point that does not fit the trend. If the data have one or more influential points, perform the regression analysis with these points. O D. An influential point is an outlier whose presence or absence has a large effect on the regression analysis. If the data have one or more influential points, perform the regression analysis without these points. b. Choose the correct answer below. O A. The coefficient of determination is the square root of the correlation coefficient, r. The coefficient of determination measures how much of the variation in the response variable is explained by the explanatory variable. O B. The coefficient of determination is the square of the correlation coefficient, r. The coefficient of determination measures how much of the variation in the response variable is explained by the explanatory variable. O C. The coefficient of determination is the reciprocal of the correlation coefficient, r. The coefficient of determination measures the direction of the linear association between two numerical variables. O D. The coefficient of determination is the square of the correlation coefficient, r. The coefficient of determination measures the strength of the linear association between two categorical variables. c. Choose the correct answer below. O A. Extrapolation is using the regression line to make predictions beyond the range of y-values in the data. Extrapolation should not be used. O B. Extrapolation is using the regression line to make predictions beyond the range of x-values in the data. Extrapolation is appropriate if there are no influential points in the data. OC. Extrapolation is using the regression line to make predictions beyond the range of x-values in the data. Extrapolation should not be used. O D. Extrapolation is using the regression line to make predictions beyond the range of x-values in the data. Extrapolation is always appropriate to use.