1) The Industrial Revolution, which began in the 18th century, brought about significant changes in agriculture, manufacturing, mining, and transportation.

2) The assassination of Archduke Franz Ferdinand of Austria in 1914 triggered the start of World War I.

3) The Mariana Trench in the western Pacific Ocean is the deepest part of the world's oceans, reaching a depth of approximately 36,070 feet (10,994 meters).

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