Consider a binomial world in which the current stock price of 80 can either go up by 10 percent or down by 8 percent. The risk-free rate is 4 percent. Assume a one-period world. Answer questions 12 through 15 about a call with an exercise price of 80. Now extend the one-period binomial model to a two-period world. Answer questions 16 through 18. a) What is the value of the call if the stock goes up, then down? b) What is the hedge ratio if the stock goes down one period? c) What is the current value of the call? Show your work