Write a user-defined function to calculate a firm's return on equity using the DuPont method as defined by (4-29) on page 125. You will need the function to accept three arguments: the net profit margin, total asset turnover ratio, and the debt ratio. Now, write another function to calculate the extended DuPont ROE as defined in equation (4-33) on page 126. This second function will require five arguments: the operating profit margin, interest burden, tax burden, total asset turnover, and the debt ratio.