Rubichau Inc. repur leu lhe following resulls Turri last year's operations: Sales Variable expenses Contribution margin Fixed expenses Net operating income Average operating assets $6,389,898 4,930,000 1,370,000 883,000 $ 567.898 $3,000,000 Al the beginning of this year, the company has a $900,000 investment opportunity with the following characteristics: Sales Contribution margin ratio Fixed expenses $1,530,869 30% of sales $ 386, eea The company's minimum required rate of return is 20% If the company pursues the investrient opportunity and otherwise performs the surrc as last year, the combined ROI for the entire company will be closest to: Multiple Choice 3.9% 240% 1459 18.5%