I posted a short survey of how people remember pitches without a reference note. This came about when a Redditor asked what key people sing “Happy Birthday” in (the correct answer being the key that the first/loudest singer chooses).
I, like most people, don’t have perfect pitch, and if someone sits at a piano and plays a popular song, I can’t tell what key they’re playing unless I see their hands. My “movable do” adapts immediately. Problem one for this survey is that, for me (and I’m assuming most others), tonality is “sticky.” Play C – G7 and ask me to sing a song, and it’s likely to come out in C or A minor. After a little longer maybe a closely related key like G or F.
I try to fight that in the survey by asking participants to listen to this “music” between questions. This is one track of Cm – Bdim7 slowly pitch shifted up two whole tones and another of Em – D#dim7 slowly pitch shifted down two whole tones, just trying to disorient the listener.
Anyway, the “answers” are below, but remember there’s no harm in being “wrong”. Perfect pitch memory/recognition is helpful at some tasks in music transcription, but relative pitch is the crucial one that allows you to enjoy and create the vast majority of Western music, recognize when notes are sharp/flat, etc.