What are the most important topics to cover during music studies for high school?

What is the following ?

It depends on what type of third separates the three notes.for example: if you have two mayor thirds is an "aumented chord"if you have two minor thirds is an "diminued chord"if you have one mayor first and then one minor is a "mayor chord"and inverted is a "minor chord"

Ithink he answer is prolly a

  i dont now so face : (.