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9. Agold mine produces 10,000 tons during year 1, 20,000 tons during year 2, 30,000 tons during year 3 and 20,000-tons during year 4. It was purchased for $100 million and can be sold at the end of four years for $40 million. Using Unit of production method, what is the depreciation during year 3? a. $22,500,000 b. $15,000,000 c. $7,500,000 d. $35,000,000 10. For question 9 above, what is the book value at the end of year one? a. $95,000,000 b. $87,000,000 c. $92,500,000 d. $77,777,777