19.Which of the following formulas computes residual income? a. Residual Income = After-tax Operating Income / (Actual Percentage Cost of Capital Total Capital Employed) b. Residual Income = Operating Income (Minimum Rate of Return Average Operating Assets) c. Residual Income = Operating Income / Average Operating Assets d. Residual Income = Operating Income Return on Investment e. Residual Income = (Minimum Rate of Return Average Operating Assets) / Operating Income