If you encounter a question on social media channels to which you don’t

dismissively – if you don’t know the answer to a question, it’s likely not an important concern
honestly – explain you don’t have an answer, but that you’ll get back to them with it
vaguely – it’s best to avoid admitting to customers that you don’t know the answer
confidently – it’s best to take your best guess at an answer, and convey it with confidence