The first portion of this has been answered but I got a different answer for the mine opening immediately, I got $2,469,450.19 for the NPV of opening the mine immediately which doesnt match the answer in Chegg could you tell me where I went wrong? My NPV for waiting a year does match the chegg answer. Also I really need help with the Black-Scholes model. PLEASE HELP!

1. Hickock Mining is evaluating when to open a gold mine. The mine has 60,000 ounces of gold left that can be mined and mining operations will produce 7,500 ounces per year. The required return on the gold mine is 12% and it will cost $14 million to open the mine. When the mine is opened, the company will sign a contract that will guarantee the price of gold for the remaining life of the mine. If the mine is opened today, each ounce of gold will generate an after tax cash flow of $450 per ounce. If the company waits one year, there is 60% probability that the contract price will generate an after tax cash flow of $500 per ounce and a 40% probability that the after tax cash flow will be $410 per ounce. What is the value of the option to wait using the option valuation/decision tree method? Suppose the minimum required rate of return (i.e. the risk free rate) for Hickock Mining is 7.5% with a variance of 10.5. Verify the direction of your results if the Black-Scholes model is applied in the decision making process.