1) In Norse mythology, the Valkyries are divine maidens who serve Odin, the chief god. They are responsible for selecting warriors worthy of entering Valhalla and escorting them to the afterlife. They are often depicted as powerful and beautiful figures, riding winged horses and wielding spears.

2) The book series "The Chronicles of Narnia" by C.S. Lewis has sold over 100 million copies worldwide.

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

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