Todays price of Marriot (MAR) is $75. MAR does not pay dividends. Each year, the stock price of MAR can either go up or down. If the stock price goes up, the gross rate of return is u = 2. If the stock price goes down, the gross rate of return is d = 0.5. The c.c. risk-free interest rate is zero percent. You are interested in a European put option on MAR with a strike of $80 and a maturity of two years. Assume there is no arbitrage.

What is the price of the put option?