4 Barefoot Industrial acquired a new delivery truck at the beginning of its current fiscal year. The truck cost $27,000 and has an estimated useful life of four years and an estimated salvage value of $4,600. Required: 6-1. Calculate depreciation expense for each year of the truck's life using Straight-line depreciation Depreciation expense per year a-2. Calculate depreciation expense for each year of the truck's life using Double-declining balance depreciation. Year Depreciation Expense 1 2 3 4 b. Calculate the truck's net book value at the end of its third year of use under each depreciation method. Net book value Depreciation method Straight-line depreciation Double-declining-balance depreciation