A company used straight-line depreciation for an item of equipment that cost $15,600, had a salvage value of $3,600 and a six-year useful life. After depreciating the asset for three complete years, the salvage value was reduced to $1,560 but its total useful life remained the same. Determine the amount of depreciation to be charged against the equipment during each of the remaining years of its useful life: Martin Company purchases a machine at the beginning of the year at a cost of $70,000. The machine is depreciated using the double-declining-balance method. The machine's useful life is estimated to be 4 years with a $5,800 salvage value. The machine's book value at the end of year 3 is