E$11\mathrm{.}11($LO $1,2)($Depreciation$-$Change in Estimate$)$ Machinery purchased for $$60,000$ by Tom Brady Co$.$ in $2016$ was originally estimated to have a life of $8$ years with a salvage value of $$4,000$ at the end of that time. Depreciation has been entered for $5$ years on this basis. In $2021,$ it is determined that the total estimated life should be $10$ years with a salvage value of $$4,500$ at the end of that time. Assume straight$-$line depreciation.

Instructions

a$.$ Prepare the entry to correct the prior years' depreciation, if necessary.

b$.$ Prepare the entry to record depreciation for $2021.$