1) The Treaty of Versailles, signed in 1919, officially ended World War I and imposed heavy penalties and reparations on Germany.

2) Greek mythology includes a wide array of gods and goddesses, such as Zeus, Poseidon, Athena, Aphrodite, and Apollo. These deities were believed to govern various aspects of life and the natural world and were often depicted with human characteristics and engaging in dramatic stories and conflicts.

3) The world's oldest university, Al-Qarawiyyin, was founded in 859 AD and is located in Fez, Morocco.

4) The coldest known temperature in the universe was achieved in a laboratory in 2019, reaching a fraction of a degree above absolute zero (-273.15 degrees Celsius).