Wexford Co. purchased a new delivery truck at the beginning of 2017. The truck has a cost of $37,000, an estimated life of five years, and an estimated residual value of $7,000. A full year's depreciation expense is to be recorded in 2017. The truck was driven 20,000 miles during 2017 and 24,000 miles during 2018. The number of expected miles over five years is 100,000. Refer to the information for Wexford Co. By what amount would double-declining-balance depreciation exceed straight-line depreciation over the five-year life of the truck? a. $7,000 b. $6,000 c. $37,000 d. $0