Equipment with a cost of $7,989, an estimated residual value of $6,789, and an estimated Me of 12 years was depreciated by the straight-line method for 7 years. Due to obsolescence, it was determined that the remaining useful life should be shortened by 3 years and the residual value changed to zero. The depreciation expense for the current and future years is 250311.17 b. 54736667 c. 10,35519 d. 54.062 .23