1) The concept of sovereignty refers to the supreme authority and power of a state to govern itself, make decisions, and control its own territory without interference from external forces.

2) The windshield wipers were invented by a woman named Mary Anderson in 1903.

3) The Berlin Conference in 1884-1885 divided Africa among European powers and set the stage for the colonization of the continent.

4) The word "pizza" contains two vowels: I and A.