In my experience being asked questions you can retrieve from memory aren't too distracting. Questions you need to even fractionally think about however cause the whole house of cards to come down.
"Did you see my email about thing?" is going to get a prompt no from me. "What's 3*9" is going to get you about 30 seconds of huhs and hold-ons before I realize it's an unimportant question (at which point it's too late to recover).
"Did you see my email about thing?" is going to get a prompt no from me. "What's 3*9" is going to get you about 30 seconds of huhs and hold-ons before I realize it's an unimportant question (at which point it's too late to recover).