Music box in B♭ major

The task

Compose a music-box piece in Bb major, 112 BPM moderato, 3/4, about 96 bars and about three and a half minutes, scored for music box in 1 voices. Texture: a thin high single-line melody over simple triads. Open with 4 bars establishing the accompaniment before the melody enters on an upbeat. The main section runs on…