My typical response to if I don't know a question is either A, to go first to my manager, well that's my last thing. First thing is I think the question over, ask the client or customer for some clarification, and then try my best initially by myself to attempt to solve their problem, answer their question. Or I will either ask my coworker or I will ask my manager as well for the question. However, if asking my coworker for help doesn't work out or even they don't know the answer, I will then proceed to hand the customer over to my manager who will try to answer the question the best way he or she can.