84
Lesson 84 of 84 · U.S. Regions
Mountain Ranges of the U.S.
Erosion — wind, water, and ice wearing away rock — shapes landscapes. The Grand Canyon was carved by the Colorado River over millions of years.
Key Facts
1
Geography affects how people live.
2
Earth has seven continents.
3
There are five major oceans.
Check Your Understanding
Question 1
1 of 2Which is the largest ocean?