A.A company has a copper mine in South Africa. It purchased the mining rights ten years ago for $20 million and has been operating the mine for the past ten years. It is estimated that there are about 8 million tons of copper in the mine. Because of a fall in world copper prices, the company has closed the mine indefinitely. At current world copper prices, the mine is uneconomic because the costs involved in extracting the copper are greater than the selling price. As the mine is in a remote and unpopulated areas there is no alternate use and it would not be able to be sold. If copper prices rise by more than 25 per cent, the company has stated that the mine would be reopened. In the foreseeable future (next 10 years or so) it is estimated there is a 20% probability that copper prices will rise sufficiently for extraction to be profitable.