When WTA, Inc. purchased rights to extract silver from a mine for a total price of $2.1 million 3 years ago, the estimated 350,000 ounces of silver was to be removed over the next 10 years. A total of 175,000 ounces has been removed and sold thus far.

(a) What is the total cost depletion allowed over the 3 years?

(b) New exploratory tests indicate that only an estimated 100,000 ounces remain in the veins of the mine. What is the cost depletion factor applicable for the next year?