Answer:
because arena's seats are all around the stage. Therefore if they want to use the drape they would have to construct it all around the stage which can be expensive and difficult.
Explanation:
I would like to say, loudness. Due to amplitude being the intensity of the wave.
what about the song
1. Melodic Range
2. Should be poly.
3. Modulation
4. I believe it's either the Timpani or a Steel Drum, I'm not quite sure. Leaning toward Timpani.
Hope this helps somehow!