The US entered World War I in:
Pearl Harbor was attacked on:

Martin Luther King Jr. is best known for:

The graph shows U.S. unemployment during the Great Depression. Based on the graph, unemployment peaked in 1933 at 25%. Which program was primarily responsible for the eventual decline?

Rosa Parks is famous for:

The diagram shows the structure of the United Nations, founded in 1945. What was the primary purpose of creating the United Nations after World War II?

The Civil Rights Act of 1964:

D-Day (June 6, 1944) was:
The Dust Bowl occurred primarily in: