Depreciation Methods Gruman Company purchased a machine for $198,000 on January 2, 2016. It made the following estimates: Service life 5 years or 10,000 hours Production 180,000 units Residual value $ 18,000 In 2016, Gruman uses the machine for 1,700 hours and produces 50,000 units. In 2017, Gruman uses the machine for 1,200 hours and produces 32,000 units. If required, round your final answers to the nearest dollar. e. Activity method based on units of output 2016 $ 2017 $ 32,000 2. For each method, what is the book value of the machine at the end of 2016? At the end of 2017? a. Straight-line method 2016 $ 162,000 2017 $ 126,000 b. Sum-of-the-years'- digits method 2016 $ 138,000 2017 $ 90,000 C. Double-declining-balance method 2016 $ 118,800 2017 $ 71,280 d. Activity method based on hours worked 2016 $ 2017 $ e. Activity method based on units of output 2016 $ 2017 $