Best Diamond Couses a perpetual inventory system and the specific identification cost formula, Below is the company's beginning Inventory.purchases and sales transactions for the month of December Quantity Unit Cost Unit Cost Beginning Inventory Dec 1) Diamond # 234 Diamond # 435 Diamond #654 Jan 6 Purchase Diamond # 765 1 2 1 $1,200 2.400 3.500 $1200 4800 3,500 1 4500 4500 Jan 4 Sold Diamond #654 for $4000 Jan 15 Sold one Diamond # 435 for $3,000 and Diamond # 234 for $2,000