Presented below is selected information for three regional divisions of Medina Company. Divisions North West South Contribution margin $300,600 $499,300 $399,100 Controllable margin $139,500 $360,800 $210,000 Average operating assets $930,000 $1,640,000 $1,400,000 Minimum rate of 13 % 14 % 8 % return Compute the return on investment for each division. North Division % West Division % South Division %