1) Brad Pitt is an American actor and film producer. He has starred in a wide range of films, including "Fight Club," "Inglourious Basterds," and "Once Upon a Time in Hollywood," and has received critical acclaim and numerous awards for his performances.

2) The blue whale is the largest animal to have ever existed, with an average length of about 82 feet (25 meters).

3) The Danube River, flowing through ten countries in Central and Eastern Europe, is the second-longest river in Europe. It has played a significant role in the cultural and economic development of the regions it traverses and is a popular waterway for river cruises.

4) The ancient city of Pompeii was preserved under layers of volcanic ash after the eruption of Mount Vesuvius in 79 AD, providing valuable insights into Roman life.