1) The name "Bluetooth" comes from the 10th-century Danish king, Harald Bluetooth, who united Denmark and Norway.

2) The blue whale is the largest animal to have ever existed, with an average length of about 82 feet (25 meters).

3) Leonardo DiCaprio is an acclaimed American actor and environmental activist. He has starred in numerous successful films, including "Titanic," "The Revenant," and "The Wolf of Wall Street," and has been recognized with several awards, including an Academy Award.

4) The banking industry is regulated by government agencies to ensure the stability and integrity of the financial system and to protect consumers.