Machinery purchased for $62,400 by Marigold Co. in 2021 was originally estimated to have a life of 8 years with a salvage value of $4,160 at the end of that time. Depreciation has been entered for 5 years on this basis. In 2026, it is determined that the total estimated life should be 10 years with a salvage value of $4,680 at the end of that time. Assume straight-line depreciation. (a) Prepare the entry to correct the prior years' depreciation,