Because when you start talking about your topic,you use to divide it,since it has to do with the 'topic',you don't use a period.
Answer:
i dont know sorry pls dont be mad at me
Subject view because if you don’t know ur subject how would you know ur content composition
In tonal Western classical music (music with a tonic key or "home key"), the most frequently encountered chords are triads, so called because they consist of three distinct notes: the root note, and intervals of a third and a fifth above the root note. ... A series of chords is called a chord progression
The Parthenon made use of the most familiar features of Greek architecture: post-and-lintel construction; a sloping, or gabled roof; and a colonnade.
