Calculate the following:

a$.$ The first year of depreciation on an office building that cost $$250,000$ purchased October $2,2023.$ This is the only placed in service this year.

b$.$ The second year $(2024)$ of depreciation on a computer that cost $$5,000$ purchased in May $2023,$ using the half$-$year convention and accelerated depreciation considering any bonus depreciation taken.

c$.$ The first year of depreciation on a computer costing $$2,800$ purchased in May $2023,$ using the half$-$year convention and straight$-$line depreciation with no bonus depreciation.

d$.$ The third year of depreciation on business furniture costing $$10,000$ purchased in March $2021,$ using the half$-$year convention and accelerated depreciation but no bonus depreciation.