Smithson Mining operates a silver mine in Nevada. Acquisition, exploration, and development costs totaled $6.3 million. After the silver is extracted in approximately five years. Smithson is obligated to restore the land to its original condition, including constructing a wildlife preserve. The company's controller has provided the following three cash flow possibilities for the restoration costs: (1) $570,000,20% probability: (2) $620,000,50% probability; and (3) $720,000,30% probability. The company's credit-adjusted, risk-free rate of interest is 7%. What is the book value of the asset retirement liability at the end of one year? Assuming that the actual restoration costs incurred after five years are $666,000, what amount of gain or loss will Smithson re