Whenever I don't know an answer to a question, I let my client know that I will double check and I will get back with them, and then I go and ask someone else that will be able to help me identify what the correct answer is because I don't like to give an answer that is incorrect to a client. I don't like to make clients upset or have to call me back, so I always want to make sure that it is very clear and that I am able to answer to the best of my knowledge.