3. At a lump-sum cost of $72,000, Pratt Company recently purchased the following items for resale: Item No. of Items Purchased Resale Price Per Unit M 4,000 $3.75 N 2,000 12.00 O 6,000 6.00The appropriate cost per unit of inventory is: A) (M) $6.00; (N) $6.00; (O) $6.00 B) (M) $3.11; (N) $19.86; (O) $3.32 C) (M) $3.60; (N) $11.52; (O) $5.76 D) (M) $3.75; (N) $12.00; (O) $6.00