'Let me get back to you on that in 30 minutes/tomorrow/a week' (depending on the complexity of the question at hand).

All this advice is correct, but these questions also show an opportunity to build tools to make answering some types of questions in resl time easy.

So I have written scripts to check out all repos under a given org for github, so I pre clone before meeting with them. For questions like how much of the site is such and such a thing, I wrote a thing to run some spark jobs over our logs every week or so and add some nice meta data and show it in a tabular portable and filter able format. I have even generalized the spark thing so I can answer many many questions from the logs in a day.

I tell people when I don't know, but I enhance my ability to find out (and then try to get teams to productize similar tools when I think it is of general value)

Truth be told, Claude code excels at these sorts of tools, much more than at production high thru put applications.