You are attempting to value a call option with an exercise price of $100 and one year to expiration. The underlying stock pays no dividends, its current price is $100, and you believe it has a 50% chance of increasing to $120 and a 50% chance of decreasing to $80. The risk-free rate rate of interest is 10%. Based upon your assumptions, calculate your estimate of the call option's value using the two-sate stock price method.