On January 1, Year 1, Marino Moving Company paid $48,000 cash to purchase a truck. Marino planned to drive the truck for 100,000 miles and then to sell it. The truck was expected to have an $8,000 salvage value. The truck was actually driven 40,000 miles during Year 1, 20,000 miles during Year 2, 35,000 miles during Year 3 and 10,000 miles during Year 4. If Marino uses the units-of-production method, the amount of book value shown on the Year 2 balance sheet is.