What was Columbus wrong about concerning his journey headed west to reach the east?

Somebody save the ! what was greek math and science also medicine

President of the united states has scheduled a cabinet meeting today to discuss energy policy with specific focus on pollution and global warming. given what you know of the executive branch, which group of attendees would the president most likely expect to provide up-to-date information and expert insight during this meeting?

Human beings spread all around the world over a period of millions of years. identify when humans arrived in different regions of the world. 200,000 years ago 100,000 years ago 40,000 years ago 30,000 years ago