Earth's most recent glacial period ended about [11,500 / 2.3 billion / 160] years ago. The Great Oxygenation Event began about [11,500 / 2.3 billion / 160] years ago. About [11,500 / 2.3 billion / 160] years ago carbon dioxide began increasing exponentially to unprecedented levels.

Answer 1

Earth's most recent glacial period ended about 11,500 years ago. The Great Oxygenation Event began about 2.3 billion years ago. About 11,500 years ago carbon dioxide began increasing exponentially to unprecedented levels.