Equator
The equator is the circle on the Earth's surface with a latitude of 0°, dividing the Earth into the Southern and Northern Hemispheres, and it's also the longest line of latitude on Earth.
The equator is the circle on the Earth's surface with a latitude of 0°, dividing the Earth into the Southern and Northern Hemispheres, and it's also the longest line of latitude on Earth.
Everything is a system, and every system contains systerms.