BTCUSD (Bitcoin) is trading at 30,000 now. You are a true believer of Bitcoin, while your friend doesn't believe in Bitcoin, so he offers to sell you an a bet where he will pay you 100 dollars if BTCUSD rise above 40,000 at the end of 3 months, otherwise he will pay you nothing. How much you should pay for this bet? Use a 3 periods Binomial model to price this bet like an option assuming an annual risk-free rate of 4%, u is 1.3 and d is 0.8 for each period (note d is not 1/u as there can be more upside in bitcoin than downside)