How might history been different if the cultures of Europe and the Americas had never come into contact?

What principle did president truman invoke in sending u.s. troops into south korea without first asking congress to declare war?

Iam a word that means to bring to fields and crops

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?