6. A unit of stock is valued at $100. In one year, the stock price will be either $115 or $90. The current riskless interest rate is 4%. (a) Use the expected-value equation (2.6) to price a put option on the stock that expires in 1 year with a strike price of $95. (b) Suppose another derivative has one of the future values U=0 and D=$15. Explain why V0 must be 3 the price computed in part (a). More exercise on this material can be found in the Chapter Review Exercises