The circumference of the Earth depends on how it is measured. When it is measured around the equator, it is 40,075 km (approximately, 24,901 miles), whereas, if it measured from the north pole to the south pole it is 40,008 km (approximately, 24,860 miles).
Ocean currents act much like a conveyer belt, transporting warm water and precipitation from the equator toward the poles and cold water from the poles back to the tropics.
B.around rivers and lakes
So they can have a source of food and water
Explanation:
I may be completely incorrect but I think its shifting/plates hitting each other.
