Answer:
Depletion costs = $20 million
COGS = $20 million + $10 million = $30 million
Step-by-step explanation:
When a company uses the full costing method, all the acquisition, exploration, and development costs are added into one single cost pool. This method is used by mining and oil corporations since the exploration sites are not always successful, so the costs related to unsuccessful sites is included in the costs of successful exploration sites.
The total cost pool associated to this mining venture = $40 million + $100 million + $60 million = $200 million
Since the firm estimates total reserves to be 20 million tons, then the depletion amortization per ton = $200 million / 20 million tons = $10 per ton
2 million tons were extracted this year x $10 per ton = $20 million