Exercise 15 Let S = 90 be the stock price, which after time t = 1 can only change up Su = 110 or down Sd = 80. Compute the risk-neutral probabilities of up move and down move, assuming that the risk-free interest rate r = 0.05. Price a call option with strike price 100. Price a call option with strike price 105. Price a put option with strike price 100. . Price a put option with strike price 105. Exercise 16 Use replicating portfolio method to price the call and put options in the previous Exercise 15. Exercise 15 Let S = 90 be the stock price, which after time t = 1 can only change up Su = 110 or down Sd = 80. Compute the risk-neutral probabilities of up move and down move, assuming that the risk-free interest rate r = 0.05. Price a call option with strike price 100. Price a call option with strike price 105. Price a put option with strike price 100. . Price a put option with strike price 105. Exercise 16 Use replicating portfolio method to price the call and put options in the previous Exercise 15