What was the main goal of the 15th amendment?

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

What two things did former british prime minister winston churchill affirm in his iron curtain speech?

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?