Sleepy Owl Company allows its divisions to operate as autonomous units. Their results for the current year were as follows:

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Revenues $$2,250,000$ $$500,000$ $$4,800,000$

Current assets $800,000152,5001,435,000$

Capital assets $1,000,000400,0001,750,000$

Current liabilities $350,00075,000540,000$

Net operating income $220,00060,000480,000$

After$-$tax income $143,00039,000312,000$

Weighted average cost of capital $8\mathrm{.}5\%8\mathrm{.}5\%8\mathrm{.}5\%$

Required:

a$.$ Return on sales

b$.$ Return on investment based on total assets employed

c$.$ Economic value added

d$.$ Residual income based on net operating income