2. Use the binomial method to determine the value of an American Put option at time t = 0. The American Put option expires at time t = T = 3 and has exercise price E = 10. The current value of the underlying is S(0) = 10 and the interest rate is r = 0.05. Use a time step dt = 1. Consider the case of p = 1/2 and suppose the volatility o = 0.4. Perform all calculations using a minimum of 4 decimal places of accuracy