1) 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).

2) The ozone layer, located in the Earth's stratosphere, protects us from harmful ultraviolet (UV) radiation.

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

4) The Great Barrier Reef in Australia is the largest coral reef system in the world and is visible from space.