A lot of talk about Va but in reality....who knows what their Va is on the airliner they fly. On the one I fly, it is a continuously changing number and it has been the same on the last several that I have flown.
Vb is memorized of course in knots and mach and it is less than Va for my type.
I'm sure someone will pipe up and scold me for not having all the Va speeds memorized but I suspect that there is a high percentage of competent pilots in airliners that are the same.
Try asking your other flight crewmember at a particular altitude what their present Va is and see if they know, In fact, I will ask right now to all, what is your Va at 5,000 feet ASL at max landing weight.