1) The strongest natural material known to man is spider silk. It is stronger than steel and more flexible than nylon.

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

3) The Epic of Gilgamesh, originating from ancient Mesopotamia, is one of the oldest surviving works of literature and tells the story of the heroic king Gilgamesh and his quest for immortality. It explores themes of friendship, mortality, and the relationship between humans and the divine.

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.