what is the price index?

de LEON William's Televisions produces television sets in three categories: portable, midsize, and flat-screen. On January 1, 2020, William adopted dollar-value LIFO and decided to use a single inventory pool. The company's January 1 Inventory consists of: Category Quantity Cost per Unit Total Cost Portable 5,400 $100 $540,000 Midsize 7,200 250 1,800,000 Flat-screen 2,700 400 1,080,000 15,300 $3,420,000 During 2020, the company had the following purchases and sales. Quantity Quantity Selling Price Category Purchased Cost per Unit Sold per Unit Portable 13,500 $110 12,600 $150 Midsize 18,000 300 21,600 400 Flat-screen 9,000 500 5,400 600 40,500 39,600