21.9. Future prices of a stock are modeled with a 2-period binomial tree, each period being three months. You are given: (i) The tree is constructed based on forward prices. (ii) The initial stock price is 20. (iii) The continuously compounded risk-free interest rate is 5%. (iv) The stock pays continuous dividends proportional to its price at a rate of 3%. (v) 0 = 0.5. Calculate the risk-neutral probability of an increase in stock price in the first period