1) The ozone layer, located in the Earth's stratosphere, protects us from harmful ultraviolet (UV) radiation.

2) The national flower of Japan is the cherry blossom, which holds great cultural significance and is celebrated during the annual cherry blossom festivals.

3) The concept of compound interest can be attributed to the ancient Babylonians, who used it in their banking practices.

4) The world's largest desert is the Sahara Desert in Africa, covering an area of about 3.6 million square miles (9.4 million square kilometers).