Research about music of civilizations contemporary to romans (who gives the best explanation i will mark brainlist)

The music in Roman society As data common to all art forms (music, sculpture and architecture), we note that the Roman people copied what the Greeks developed and adapted to their needs.

including the octave, the answer would 8 notes in a major scale with one note being played twice. ex) c major scale includes: c, d, e, f, g, a, b, c

notice that c is played twice

however, if you were to ask me how many different notes are in a major scale- the answer would be 7.  

answer/// priests singing psalms and the congregation singing responses;