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Lesson 13 of 84 · Westward Expansion
The Mexican-American War
The Columbian Exchange transferred plants, animals, diseases, and ideas between the Americas and Europe after 1492. Potatoes went to Europe; horses and wheat came to the Americas.
Key Facts
1
Historians use evidence to support claims.
2
Timelines show events in order.
3
Cause and effect explain why things happen.
Check Your Understanding
Question 1
1 of 2Why do we study history?