I always laugh when I remember my mum doing a Les Dawson imitation whenever she used to "period". Y'know, the way he used to say a word without making a sound?!
No if you don't know the answer how can the question be stupid.
I remember years ago on a course at the start the course leader said to us all if there is something you don't know please don't be scared to ask chances are other people in the room will have the same question but are to scared to ask.