Use the binomial tree technique to solve these two problems:

1. A stock trades at a price of $30, and will pay a dividend of $2 in 4 months time. The stock has a volatility of 16%, and interest rates are 4% (with continuous compounding). Price a one year American put option with strike price $25. Use a two step tree, with 6 month time steps.

2. Price a 6 month American call option with strike price 1100, written on a 2 year futures contract on oil. Volatility is 18%. Interest rates are 5% (with continuous compounding). The current futures price is 1050. Use a two step tree, with 3 month time steps.