3. If Gruman used a service life of 8 years or 15,000 hours and a residual value of $10,000, what would be the effect on the following under the straight-line, sum-of-the-years'-digits, and double-declining-balance depreciation methods? Depreciation expense a. Straight-line method 2016 $ 26,250 2017 $ 26,250 b. Sum-of-the-years'-digits method 2016 $ 46,667 2017 $ 40,833 c. Double-declining-balance method 2016 $ 55,000 2017 $ 41,250 Book value a. Straight-line method 2016 $ 193,750 2017 $ 167,500 Book value a. Straight-line method 2016 $193,750 2017 $ 167,500 b. Sum-of-the-years'-digits method 2016 $ 153,333 X 2017 $ c. Double-declining-balance method