Asking about these question below. Please give me detailed explanation and proper answer in Excel. Thanks so much!

11. The current price of Estelle Corporation stock is $25. Its stock price will either go up by 20% or go down by 20% in one year. The stock pays no dividends. The one-year risk-free interest rate is 6%. Using the binomial model, calculate the price of a one- year call option on Estelle stock with a strike price of $25. 12. Using the information in Problem 11, use the binomial model to calculate the price of a one-year put option on Estelle stock with a strike price of $25. a