Equipment with a cost of $75,489, an estimated residual value of $5,141, and an estimated life of 14 years was depreciated by the straight-line method for 6 years. Due to obsolescence, it was determined that the remaining useful life should be shortened by 4 years and the residual value changed to zero. The depreciation expense for the current and future years is a 33,23856 Ob 511,33496 Oc. 530,149.14 Od 54.531.99