Earth can be divided into four major spheres: biosphere, hydrosphere, atmosphere, and
a lithosphere

b hemisphere

c geosphere

The answer is C.geosphere

Explanation:

Geographers break down the Earth's systems into four spheres that make up the world's air (atmosphere), water (hydrosphere), land (geosphere), and living organisms (biosphere).

the answer would be the third option, "no, ariel should have added 9^2 and 12^2 and compared that to 15^2."

this is found through the pythagorean theorem, which is a^2 + b^2 = c^2.

this is the correct way of solving the problem:

9^2 + 12^2 = 15^2

81 + 144 = 225

225 = 225