1) The world's largest ocean, the Pacific Ocean, covers an area of approximately 63 million square miles.

2) The Serengeti National Park, located in Tanzania and extending into Kenya, is renowned for its vast savannahs, diverse wildlife, and the annual wildebeest migration. It is a UNESCO World Heritage site and a popular destination for safari enthusiasts and nature lovers.

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

4) The word "cheese" contains three vowels: E, E, and E.