Answer:
a. Controllable margin = Sales - Variable costs - Controllable fixed cost
=5,500,000 - 2,200,000 - 2,540,000
= $760000
b. Return on Investment (ROI) = Controllable margin / Average Operating Assets * 100
= 760,000 / 4,000,000 * 100
=0.19 * 100
=19%
c. Residual income = Controllable margin - Minimum required return (4000000 * 16% = 640000)
=760,000 - 640,000
=$120,000