47 Martin Company purchases a machine at the beginning of the year at a cost of $71,000. The machine is depreciated using the straight-line method. The machine's useful life is estimated to be 4 years with a $4,000 salvage value. The book value of the machine at the end of year 4 is: Skipped Multiple Choice $4,000. 0 $o. 0 $35,500. 0 $16,750. 0 $67,000