In 1917 when the U.S. entered the war the central powers realized they were too weak because they were running out of men. Also they were in econoic trouble so they couldn't afford to keep fighting. So they came to the agreement of The Treaty of Versailles.
I think that Henry Fords system of production affect other industries in a good way by interduching the line
La mitad de 40 es 20 porque 20,40 mitad 2 es 20
C is similar to the preamble to the US constitution