1) The Great Wall of China is not visible from space without aid, contrary to popular belief.

2) The Mariana Trench in the western Pacific Ocean is the deepest part of the world's oceans, reaching a depth of approximately 36,070 feet (10,994 meters).

3) The Federal Reserve System, often referred to as the Fed, is the central banking system of the United States.

4) The word "pencil" contains two vowels: E and I.