Examlex
During the ____________________, about 2.4 billion years ago, oxygen concentration in the atmosphere increased to appreciable quantities.
Truman
Truman refers to Harry S. Truman, the 33rd President of the United States, who served from 1945 to 1953, known for ending World War II by authorizing the use of atomic bombs against Japan.
Historians
Scholars who study and write about the past, interpreting historical sources and events.
Nation's Presidents
The elected leaders who have served as the head of state and government in a country's history.
Suburbs Growth
The expansion of residential areas outside the urban core, typically characterized by single-family homes, which became increasingly prevalent during the 20th century.
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