Our atmosphere is the largest
a. transport and distribution system on earth
b. sphere of earth
c. atmosphere compared to other planets
d. reservoir of liquid water on earth

The answer is A. Our atmosphere is the largest transport and distribution system on Earth.  It is a critical system that regulates climate here on Earth and distribute the heat. It is a very essential part of our planet. Its very existence makes Earth habitable. The atmosphere is a very complex system which contains a lot of physical and chemical reactions to maintain balance on Earth.

It is useful for historians to write narratives so that history can be passed on from their point of view.  think about a story being told in third person, then think about it again being told in first person, by someone who actually experienced the event.

Why the planet stays in orbit is because of inertia (object stays in motion until a force changes it’s motion) also the atmosphere and gravity!