music: 70's Chart Toppers: Name The Artist: Ball Of Confusion?

Questions

(It., 'obligatory') - An obbligato part is one which has an important and unusual special role and cannot be dispensed with, as opposed to an optional part. However, in some l9th century music, the term obbligato was applied to an additional optional part.?

- Describes the movement of parts or melodies when one remains on the same note and the other moves in some direction.?

- The interval of eight steps (e.g. C to C on the white notes of the piano).?

- A composition for eight voices or instruments, or simply eight people.?

- The setting of a poem entitled 'ode' to music.?