How many questions do you have to answer to get a higher in your rank on WikiAnswers?

You do not have to answer a certain amount of questions to upgrade your ranking on WikiAnswers. Any type of contribution will work to get you to the next rank. (Contribution types: messaging, editing, answering, or removing an answer, splitting and adding alternates, asking a question, and editing categories can get you contribution points. See the question "What are the various contributor levels on WikiAnswers" to see the next level you will become.