1) The world's first paper money was created in China over 1,000 years ago.

2) The fastest recorded serve in tennis was achieved by Sam Groth at 163.7 miles per hour (263.4 kilometers per hour) during a tournament in 2012.

3) The Atlantic Ocean is the second-largest ocean and is known for its strong ocean currents, including the Gulf Stream.

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