I had the same idea, but in an SQL Fiddle

http://sqlfiddle.com/#!1/778bb/5

Didn't even know that there was such a thing as SQL Fiddle. That's going to come in handy, beyond this quiz, thanks.

In the same vain here are some very quickly put together answers if anyone is interested. I haven't tested these so they may not work. If you see any errors please let me know :)

https://gist.github.com/dritterman/5662750