Metlock Company constructed a building at a cost of $$2,420,000$ and occupied it beginning in January $2006.$ It was estimated at that time that its life would be $40$ years, with no salvage value.

In January $2026,$ a new roof was installed at a cost of $$330,000,$ and it was estimated then that the building would have a useful life of $25$ years from that date. The cost of the old roof was $$176,000.$

$($a$)$

What amount of depreciation should have been charged annually from the years $2006$ to $2025?($Assume straight$-$line depreciation.$)$

Depreciation per year