Determining missing items in return on investment computation One item is omitted from each of the following computations of the return on investment: Return on Investment = Profit Margin Investment Turnover x 10 % x (a) 16 % 0.75 x 25 % (b) 18 % 10 % (e) = = 1 x 1.5 (C) 20 % 15 % X x x x (d) x Determine the missing items identified by the letters as shown above. If required, round your answers to two decimal places. (a)