Please explain this problem. Thank you :)

At a lump-sum cost of $18,000, Obenauer Company recently purchased the following items for resale: Item ABC QRS XYZ No. of Items Purchased 2,000 1,000 3,000 Resale Price Per Unit $5.00 $8.00 $2.00 The appropriate cost per unit of ABC inventory is: Select one: O a. $3.00 b.$.80 O O c. $1.50 d. $3.75 O e. $2.40 x