Answer: The term "function" was introduced by Gottfried Wilhelm Leibniz (1646-1716) almost fifty years after the publication of Geometry. The idea of a function was further formalized by Leonhard Euler (pronounced "oiler" 1707-1783) who introduced the notation for a function, y = f(x).
The event that occurred in the 4th Crusade was the Crusaders attacked Constantinople. The sack of Constantinopea took place in April 1204, during the 4th Crusade. The Crusaders attacked, destroyed and robbed during the assault of Constantinople. (Hope this helps! :)
The 26th amendment expanded the right to vote. It made it so that you had to be 18 or older to vote.
The withdrawal allowed Germany to make great gains on the Western Front.