Xulu Company Had the Following Income Statement for Last Year

Xulu Company had the following income statement for last year: $$\begin{array} { l r } \text { Sales } & \$ 400,000 \\\text { Less: Cost of goods sold } & 220,000 \\\text { Gross profit } & \$ 180,000 \\\text { Less: Selling and administrative expense } & 80,000 \\\text { Operating income } & \underline { \$ 100,000 } \\\hline\end{array}$$ Beginning assets were $575,000, and ending assets were $625,000.
Required:
(Carry computations out to three decimal places.)
A. Calculate the average operating assets.
B. Calculate the margin.
C. Calculate the turnover.
D. Calculate the ROI.