1) The hibiscus flower is commonly associated with tropical regions and is the national flower of several countries, including Malaysia, South Korea, and Haiti.

2) The process of photosynthesis, performed by plants, algae, and some bacteria, is responsible for producing the oxygen we breathe.

3) The world's first credit card was introduced in 1950 by Diners Club.

4) The Earth's core is hotter than the surface of the Sun.