What effect do the Rocky Mountains have on rivers and streams

The Rocky Mountain Trench separates the main geological body of the Canadian Rockies and the additional Columbia Mountain group. The Rocky Mountain Trench drains into several of the main rivers, such as the Peace River, Kootenay River, Fraser River, and Columbia River.

Explanation:

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