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

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

3) The world's oldest known living tree is a bristlecone pine named "Methuselah" in California, estimated to be over 4,800 years old.

4) The Victoria Amazonica water lily has leaves that can grow up to 10 feet (3 meters) in diameter, making it one of the largest aquatic plants.