on april 17, 2024, the loadstone mining company purchased the rights to a copper mine. the purchase price plus additional costs necessary to prepare the mine for extraction of the copper totaled $2,910,000. the company expects to extract 970,000 tons of copper during a four-year period. during 2024, 350,000 tons were extracted and sold immediately. required: calculate depletion for 2024. is depletion considered part of the product cost and included in the cost of inventory?