1) The tongue of a blue whale is so big that about 50 people could stand on it.

2) The word "mountain" contains three vowels: O, U, and A.

3) The concept of compound interest can be attributed to the ancient Babylonians, who used it in their banking practices.

4) Norse mythology, originating from the Scandinavian region, features gods and mythical creatures like Odin, Thor, Loki, and Valkyries. It explores themes of heroism, destiny, and the battle between gods and giants, with intricate tales recorded in texts such as the Prose Edda and Poetic Edda.