We model the price of a non-dividend-paying stock as a two-step binomial tree model with time step being 6 months. Currently, the price of this stock is $100 per share. At each time step the stock price will go up or down by 5%. Suppose that the risk-free rate is always 5% per annum with continuous compounding. What is the price of a 1-year American put option with a strike price of $104 on this stock?