Able Towing Company purchased a tow truck for $180,000 on January 1, 2017. It was originally depreciated on a straight-line basis over 10 years with an estimated salvage value of $36,000. On January 1, 2019, the company decided to change the remaining estimated life to 4 years (including 2019) and the salvage value to $5,000. What is the new annual depreciation expense for the tow truck beginning in 2019? a. $18,000. b. $14,400. c. $45,000. d. $36,550