QRS Co$.$ has four operating divisions with the following information for the most recent fiscal year:

Division A Division B Division C Division D

Sales $$12,000,000$ $$14,000,000$ $$25,000,000$ $$10,000,000$

Net operating income $$600,000$ $$560,000$ $$800,000$ $$720,000$

Average operating assets $$3,000,000$ $$7,000,000$ $$5,000,000$ $$6,000,000$

The minimum rate of return set by company management is $15\%.$

Required:

a$.$ What is the return on investment for each division?

b$.$ If Division B was able to reduce its operating expenses by $$70,000,$ what would be its new return on investment?

c$.$ What is the residual income for each division?

d$.$ If the divisions were each offered an opportunity to add an investment that would result in a $17\%$ ROI, which division would be less likely to accept the new opportunity?