1) A single bolt of lightning can heat the surrounding air to temperatures five times hotter than the surface of the sun.

2) International relations encompass the study of relationships between nations, including diplomacy, treaties, and foreign policy. It examines the interactions and dynamics among different countries in the global arena.

3) Johnny Depp is an American actor and producer known for his unique and versatile performances in films such as the "Pirates of the Caribbean" series, "Edward Scissorhands," and "Sweeney Todd: The Demon Barber of Fleet Street." He has received multiple accolades for his work.

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