For its three investment centers, Gerrard Company accumulates the following data: I II III Sales $1,900,000 $3,900,000 $3,900,000 Controllable margin 784,000 1,817,000 3,600,000 Average operating assets 4,900,000 7,900,000 12,000,000 Compute the return on investment (ROI) for each center. I II III The return on investment % % %