Lots of questions on different subjects where you have to try to answer the latest question and if you are right then its your turn to ask the next question.
I think you mean you'd have looked it up on Google earlier - that's different to answering it. The forum rules are very clearly explained in Jus's "Read this or else" - I admit I've often been guilty of not posting questions in a timely fashion but that's an oversight. If someone takes the trouble to research and set a question then I don't think it's unreasonable to ask people to answer it using their own knowledge - if it goes for 3-4 days unanswered then fair enough, use a search engine.
I could never forget this as I once second guessed a notoriously bad question master to win a quiz with this fact. His question was "Which famous scientist invented the flat cap?" Our answer was Isaac Newton on the basis that a) he invented the cat flap and b) the QM was a known idiot.