Mohr Company purchases a machine at the beginning of the year at a cost of $30,000. The machine is depreciated using the double declining-balance method. The machine's useful life is estimated to be 5 years with a $5,000 salvage value. The machine's book value at the end of year 2 is: Multiple Choice $15,000 $9.000 O O $18,000 $10.800 $12.000