1) The world's oldest university, Al-Qarawiyyin, was founded in 859 AD and is located in Fez, Morocco.

2) The world's most expensive car is the Bugatti La Voiture Noire, which sold for over $18 million.

3) The word "book" contains two vowels: O and O.

4) Sir Elton John, born Reginald Kenneth Dwight, is an English singer, songwriter, and pianist. With a career spanning over five decades, he is one of the best-selling music artists in the world and has received numerous awards and accolades for his contributions to music.