Help Please

Can you help me find the Dn and the Book Value ?

Calculate the depreciation stated for each asset for the first three years. For the building consider it was bought on May of Year 1.

Item Initial cost Book life MACRS class Salvage value Book depreciation Building $800,000 50 years 39 years $100,00 0 SL Building Tax Depreciation Item Initial cost Book life MACRS class Salvage value Book depreciation Building $800,000 50 years 39 years $100,00 0 SL Building Tax Depreciation