1) The smallest unit of time is known as a zeptosecond, which is equal to one trillionth of one billionth of a second.

2) The Dead Sea, located between Jordan and Israel, is the lowest point on Earth's surface. Its saltwater is so dense that people can easily float on its surface.

3) The concept of political parties allows for organized groups to mobilize support, articulate policy positions, and compete for political power through elections and political campaigns.

4) The average person walks the equivalent of three times around the world in a lifetime.