1) The Mongol Empire, under the leadership of Genghis Khan, became the largest contiguous empire in history, spanning from Asia to Europe.

2) 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.

3) The speed of light is approximately 299,792,458 meters per second.

4) The concept of insurance dates back to ancient times when merchants would distribute their goods across different ships to reduce the risk of losing everything in a single event.