OK, you got 20 questions you can ask me.
I'm going to tell you a little story, then ask you a question. You have to answer the question by asking 20 questions of your own, then telling me the answer to mine.
The questions you ask MUST be "yes or no" questions.
You cannot play if you've heard it before and already know the answer. You only get to sit around and laugh at the people who don't know it already.
Don't make this too complicated. The answers are usually pretty simple.
STORY: A man lives on the 20th floor of an apartment building. On rainy days, he goes to work by taking the elevator down to ground level, and when he comes home, he rides the elevator to the 20th floor. On sunny days, he goes to work by taking the elevator down to ground level, and when he comes home, he rides the elevator to the 10th floor and walks the rest of the way up.
Question: Why does he only ride the elevator to the 10th floor on sunny days?