Answer:
The pitch of a tone
Explanation:
Tone color, also known as timbre, is the quality of a sound that is not characterized as frequency (pitch), duration (rhythm), or amplitude (volume).
Art is something that's beautiful, it contains varies types: Visual arts, performance arts, etc.
D) Libretto
There's, 4/4, 6/6, 9/9, any fraction that equals 1
