Glorious Sun Company constructed a building for $$2,200,000$ and occupied it from January $2000.$ It was estimated at that time that its life would be $40$ years, with no residual value.In January $2020,$ a new roof was installed at a cost of $$300,000,$ and it was estimated then that the building would have a useful life of $25$ years from that date. The cost of the old roof was $$160,000.$a$.$What amount of depreciation should have been charged annually from the years $2000$ to $2019($Assume straight$-$line depreciation.$)$b$.$What entries should be made in $2020$ to record the replacement of the roof? c$.$Prepare the entries in January $2020$ to record the revision in the estimated life of the building, if necessary.d$.$What amount of depreciation should be charged for the year $2020($assume the cost of the old roof is removed$)?$