9. In 2022 , Colorado Mining Company paid $6,000,000 for a mining tract with reserves of 150,000 tons of ore, which the company planned to mine over a 20 -year period. The company spent $750,000 developing the mine. The fair value of the cost that Colorado Mining plans to spend for restoring the environment is $300,000 when mining has been completed, after which the land will have an estimated value of $450,000. In 2022, Colorado Mining mined and sold 30,000 tons of ore. What depletion should Colorado Mining record for the year? a. $1,320,000 b. $1,200,000 c. $660,000 d. $600,000