A delivery truck costing $21,000 is expected to have a $1,500 salvage value at the end of its useful life of four years or 125,000 miles. Assume that the truck was purchased on January 2. Calculate the depreciation expense for the second year using each of the following depreciation methods: (a) straight-line, (b) double-declining balance, and (c) units-of-production. (Assume that the truck was driven 28,000 miles in the second year.) Round all answers to the nearest dollar.