1) The highest mountain in Africa is Mount Kilimanjaro, standing at 19,341 feet (5,895 meters) tall.

2) The universe is estimated to be around 13.8 billion years old.

3) The concept of proportional representation, used in some electoral systems, aims to ensure that political parties' representation in government aligns more closely with the proportion of votes they receive from the electorate.

4) The Renaissance period, which began in Italy in the 14th century, marked a renewed interest in art, literature, science, and philosophy.