30
Lesson 30 of 84 · U.S. History
America in the 21st Century
Archaeology studies human history through excavation of artifacts, buildings, and physical remains. Archaeologists piece together stories from objects left behind long ago.
Key Facts
1
Timelines show events in order.
2
Cause and effect explain why things happen.
3
Oral histories preserve community stories.
Check Your Understanding
Question 1
1 of 2Which is a secondary source?