Equipment with a cost of $80,000, an estimated residual value of $5,000, and an estimated life of 15 years was depreciated by the straight-line method for 5 years. Due to obsolescence, it was determined that the useful life should be shortened by 5 years and the residual value changed to zero. The depreciation expense for the current and future years is: $11.000 $5,500 O$10,000- $5.000