Vaughn Company constructed a building at a cost of $2,398,000 and occupied it beginning in January 1998. It was estimated at that time that its life would be 40 years, with no salvage value. In January 2018, a new roof was installed at a cost of $327,000, 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 $174,400

What amount of depreciation should have been charged annually from the years 1998 to 2017? (Assume straight-line depreciation).?

What entry should be made in 2018 to record the replacement of the roof?

What amount of depreciation should be charged for the year 2018?