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

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

3) The Appalachian Mountains, running along the eastern coast of the United States, are one of the oldest mountain ranges in the world.

4) The concept of human rights advocates for the basic rights and freedoms to which all individuals are entitled, regardless of their nationality, ethnicity, religion, or other characteristics.