George runs a cookie factory. His cookies are made with sugar, peanut oil, and soybean oil. The number of boxes of cookies that he produces is f (su, po, so) = min { su; po + 2so } where su is the number of bags of sugar, po the number of canisters of peanut oil, and so the number of canisters of soybean oil that he uses. The price of a bag of sugar is 11. The price of a canister of peanut oil is 6. The price of a canister of soybean oil is 20. If George makes 254 boxes of cookies in the cheapest way possible, how many canisters of soybean oil will he use?