For the fiscal year end of $2022,$ Walmert Inc. $($WMT$)$ had revenue of $$611\mathrm{.}289$ billion, oces of sales of $$463\mathrm{.}721$ billion, and net income of $$11.680$ billion. Costro Wholesale Corporation $($COST$)$ had revemue of $$242\mathrm{.}290$ bullion, cost of sales of $$212586$ billion, and net income of $$6\mathrm{.}292$ billion.

$($a$)$ Compare the gross margin for Walmart and Costco in $2022.$

$($b$)$ Compare the net profit margin for Walmart and Costoo in $2022$

$($c$)$ Which firm was more profitable in $2022?$