QUESTION 16 When there is a change in estimated depreciation due to a change in estimated useful life or salvage value previous depreciation should be corrected only future years depreciation should be revised current and future years' depreciation should be revised Othere is no need to revise current or future years depreciation because depreciation depends upon estimates QUESTION 17 When bonds are issued at a premium, the total interest expense of the bonds over the life of the bonds is: premium at the sale point interest paid over the life of the bonds minus the amount of the premium at the sale point. interest paid over the life of the bond interest paid over the life of the bonds plus the amount of the premium at the sale point