Sunland Company uses a perpetual inventory system. The company began $2024$ with $1,500$ lamps in inventory at a cost of $$10$ per unit. During $2024,$ Sunland had the following purchases and sales of lamps:February $15$Purchased$3,000$ units @ $$16$ per unitLApril $24$Sold$3,750$ units @ $$28$ per unitJune $6$Purchased$5,250$ units @ $$21$ per unitOctober $18$Sold$3,000$ units @ $$31$ per unitDecember $4$Purchased$2,100$ units @ $$24$ per unitAll purchases and sales are on account.$($a$)$Calculate the cost of goods sold and ending inventory using weighted average. $($Round the weighted average cost per unit to $2$ decimal places, e$.$g$,5\mathrm{.}27$ and final answers to $0$ decimal places, e$.$g$.5,275.)$