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) Insurance premiums are the payments made by policyholders to insurance companies in exchange for coverage.

3) The concept of self-driving cars, or autonomous vehicles, is being actively developed by companies such as Tesla, Google (Waymo), and Uber.

4) The European Union (EU) is a supranational organization comprising 27 member states that cooperate on various issues, including trade, economic integration, and common policies, while preserving individual national sovereignty.