please help me out with the last three questions

Blaser Corporation had $1,005,000 in invested assets, sales of $1,247,000, operating income amounting to $223,000, and a desired minimum return on investment of 12%. The return on investment for Blaser Corporation is Round the percentage to one decimal place. b. 17.9% Cc. 14.3% d. 26.6% D Mason Corporation had $1,057,000 in invested assets, sales of $1,223,000, operating income amounting to $248,000, and a desired minimum return on investment of 15%. The residual income for Mason Corporation is Ca(55,600) b. 50 Oc. $125,230 Cd. $89,450 Sage Company is operating at 90% of capacity and is currently purchasing a part used in its manufacturing operations for $14,00 per unit. The unit cost for the business to make the part is $20.00, including fixed costs, and $12.00, not including fixed costs. If 38,586 units of the part are normally purchased during the year but could be manufactured using unused capacity, the amount of differential cost increase or decrease from making the part rather than purchasing it would be a a. $231,516 cost increase b. $77,172 cost decrease Oc. $77,172 cost increase Od. $540,204 cost decrease