Find online the annual$10-$K report for CostcoCostco Wholesale Corporation$($COST$)$ as of August $28$ comma $2022$August $28,2022.$

a$.$ Compute CostcoCostco$\text{'}$s net profit$$ margin, total asset$$ turnover, and equity multiplier.

b$.$ Verify the DuPont Identity for CostcoCostco$\text{'}$s ROE.

c$.$ Repeat the analysis from parts $($a$)$ and $($b$)$ using WalmartWalmart Stores$($WMT$)$ instead.$$ Specifically, use WalmartWalmart$\text{'}$s data as of January $31$ comma $2022$January $31,2022.$ Based on the DuPont$$ Identity, what explains the difference between the two$$ firms' ROE?