1) 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.

2) The world's tallest waterfall is Angel Falls in Venezuela, with a height of about 3,212 feet (979 meters).

3) The Atlantic Ocean is the second-largest ocean and is known for its strong ocean currents, including the Gulf Stream.

4) The Dow Jones Industrial Average (DJIA) is a stock market index that tracks the performance of 30 large, publicly owned companies in the United States.