Sandhill Mining Company purchased land containing an estimated $15$ million tons of ore at a cost $$4,365,000.$ The land without the ore is estimated to be worth $$615,000.$ The company expects to operate the mine for $12$ years. Buildings costing $$615,000$ are erected on the site and are expected to last for $25$ years. Equipment costing $$345,000$ with an estimated life of $15$ years is installed. The buildings and the equipment possess no salvage value after the mine is closed. During the first year of operations, the mining company mined and sold $4$ million tons of ore.

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