Making the initial investment will provide the company with the expertise that will enable it to make an investment of $400 million in 4 years from now, which prospectively will generate subsequent 5 years' of cash flows at $80 million a year. To estimate the value of the option of a follow-on investment, we use the B-S option pricing model. Assume the required rate of return on the follow-on investment is 12%. The standard deviation of the return on the asset is 30% and the interest rate is 8%. What is the value of the underlying asset S. to be used in the B-S formula to estimate the follow-on investment opportunity?