Answer:

1. In simple terms, tempo is how fast or slow a piece of music is performed, while rhythm is the placement of sounds in time, in a regular and repeated pattern. Tempo generally is measured as the number of beats per minute, where the beat is the basic measure of time in music.

2.it's comes from their minds or emotions.  because they wrote it base of their feelings and emotion and their experience of it,it could be happy,sad or other emotions.

Explanation:

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