Kleener Co. acquired a new delivery truck at the beginning of its current fiscal year. The truck cost $21,000 and has an estimated useful life of four years and an estimated salvage value of $4,500.

Required:

a-1. Calculate depreciation expense for each year of the truck's life using Straight-line depreciation.

a-2. Calculate depreciation expense for each year of the truck's life using Double-declining-balance depreciation.

b. Calculate the truck's net book value at the end of its third year of use under each depreciationmethod.