What is a good technique to use to remember information for a cumulative exam?
The best technique I have found is to create your own study guide. It helps to organize all of the different information into more manageable sections to help remember it. Also by rewriting the information, it is further solidifying it into memory.
How do I know the key signatures for all of the keys?
It is best to follow the Circle of Fifths and go around and add a sharp or flat. Start with C where there are no sharps or flats, then go to G where you have 1 sharp, the go to D where there are 2 sharps, etc.
What is considered music? Is any sound music?
Music is sound that is pleasing to the ear or other senses, and it is very subjective as to if a sound is music.