Problem 6-25 Calculating depreciation expense using four different methods O'Brian Service Company purchased a copier on January 1, 2012, for $17,000 and paid an ad- ditional $200 for delivery charges. The copier was estimated to have a life of four years or 800,000 copies. Salvage was estimated at $1,200. The copier produced 230,000 copies in 2012 and 250,000 copies in 2013 Required Compute the amount of depreciation expense for the copier for calendar years 2012 and 2012, using these methods: a. Straight-line. b. Units-of-production. S Double-declining-balance