Depends on the music. The most popular ones include timpani, triangle, cymbals, snare drum, bass drum
Check out this link.
http://takelessons.com/blog/piano-pop-songs-for-everyone-z06
Also songs from movies or plays are also good.
Answer:
People that are sad actually sleep less because they just keep waking up in middle of sleep. This disrupts the sleep cycle. Happy people get the most sleep between the two.
Explanation:
B. Masks. is the correct answer
