The notes to play as a one-bar score: to follow the playing against, and to show once answered
The notes to play, lowest or first first
Played together — a chord, a harmonic interval — or one after another
What the staff shows before it is answered — the starting note, or the note to play, after the signature for a key — or null when it is asked by ear
The note given to start from — shown on the staff and sounded — or
null when nothing is given: a note to read and play, or a question heard
and played back
A question answered by playing: what is given to start from, and the notes to play, which the playing is judged against.