1) Serena Williams, an American tennis player, has won a total of 23 Grand Slam singles titles, making her one of the most successful players in the history of the sport.

2) The total length of your blood vessels can circle the Earth more than twice.

3) The musical "Les Misérables" is one of the longest-running shows in the West End and Broadway, with over 13,000 performances.

4) The world's first car radio was invented in 1929.