The current stock price of firm AAa= $20. It is expected that this firm’s stock price will go up by 20%, or it might go down by 20%. No dividends. The one year risk free rate = 5%. A call option’s strike price is also $20. Using the binomial pricing model , calculate that to set up a risk free portfolio, for each call option, how many stocks (or portion of a stock) is needed. 22. Using the binomial pricing model, calculate the price of a one-year call option on this stock with a strike price of $20 is: