How to judge a chord from a note. For example, I know the lead for national anthem and it goes like--- SA RE GA GAGA GA GAGA GA GAGA RE GA MA. This can be played on any scale. Now, my question is how the chords are judged for a note say SA? Also, chord for which note is played? Is is that the note which comes after a certain beats is used as a root of chord or something? Thanks in advance!