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

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

3) The first computer mouse was invented by Douglas Engelbart in 1964 and consisted of a wooden shell and two metal wheels.

4) The most-watched TV series finale in the United States was "MAS*H," with an estimated 105 million viewers.