1. Imagine you are visiting a friend who lives in a huge subdivision that only has one entrance and you forgot to bring your phone. You remember that there are four stop signs and at each you take either a left or a right then at the end there is a cul-de-sac where you will recognize your friend's house. If the subdivision is designed such that every cul-de-sac is at the end of four such turns, how many cul-de-sacs at most will you have to check? Please show your (simple) equation.