The overall regression F-statistic tests the null hypothesis that: a. some slope coefficients are zero. b. all slope coefficients and the intercept are zero. c. the intercept in the regression and at least one, but not all, of the slope coefficients are zero. d. the slope coefficient of the variable of interest is zero, but that the other slope coefficients are not. e. All of the above. f. None of the above. QUESTION 14 For a single regressor model, which of the following is a true statement? a. by dividing the estimate by its standard error you obtain the t-statistic. b. the square root of the F-statistic is a t-statistic. c. the estimate is significant (at the 5% level) if the absolute value of the t-statistic is above 1.96. d. the estimate is significant (at the 5% level) if the confidence interval does not contain the zero. e. All of the above. f. None of the above