Mohr Company purchases a machine at the beginning of the year at a cost of $24,000. The machine is depreciated using the straight-line method. The machine's useful life is estimated to be 5 years with a $4,000 salvage value. The book value of the machine at the end of year 2 is: A. $20,000 B. $8,000 C. $12,000 D. $16,000 E. $4,000