A flower is an example of what kind of balance?

Flowers are replicated on opposite sides of the floral arrangement, called symmetrical balance, known as formal balance. Using an imaginary central axis, the mirror image of the other is one side of the structure. Asymmetrical equilibrium, referred to as informal harmony.

Perspective is important because it enabled the 3 dimensional world to be translated into the 2d world of the picture plane. this had an immediate impact on the representation of reality in art and design. 

His contribution to the orchestral genre mainly lies with foreshadowing ideas that are to come like the emergence of the classical symphony, the cadenza for a keyboard, and paired instrumentation;