Presented below is selected information for three regional divisions of Medina Company. Contribution margin Controllable margin Average operating assets Minimum rate of return North $300,300 $140,000 $1,000,000 11 96 Divisions West $500,100 $361,100 $1.570,000 15 % South $399,300 $208.600 $1,490,000 9 % (a) Compute the return on investment for each division. North Division 96 West Division 96 South Division