Alcar Corporation had the following results for its electronic division last year:

Sales $6,000,000

Operating income 900,000

Total liabilities 2,250,000

Total stockholders' equity 750,000

Management target rate of return is 10% and weighted average cost of capital is 7%. Whatis the division's Return on Investment(ROI)?

a. 15%.

b. 25%.

c. 30%.

d. 200%.

Note: please show answer how it is calculated.