1) The Mona Lisa, painted by Leonardo da Vinci, is one of the most famous and valuable artworks in the world.

2) The first commercially available digital camera, the Dycam Model 1, was introduced in 1990 and had a resolution of 376 x 240 pixels.

3) Cristiano Ronaldo is a Portuguese professional soccer player widely regarded as one of the greatest footballers of all time. He has won numerous awards, including multiple FIFA Ballon d'Or titles, and has played for top clubs such as Manchester United, Real Madrid, and Juventus.

4) The Dead Sea, bordered by Jordan to the east and Israel and Palestine to the west, is a hypersaline lake known for its high salt concentration. It is the lowest point on Earth's land surface and provides unique buoyancy, attracting visitors who enjoy floating in its waters.