The following data pertain to British Isles Aggregates Company, a producer of sand, gravel, and cement, for the year just

ended.

$$ denotes the British pound sterling, the national monetary unit of Great Britain.

Exercise $13-33$ Part $3$

$3-$a$.$ Assuming that the expenses and cost of goods sold are reduced in order to improve the firm's ROI to $45$ percent, compute the

firm's new sales margin.

$3-$b$.$ Show how the new sales margin and the old capital turnover together result in a new ROI of $45$ percent.