Answer: People were afraid of wild animals and people they didn’t know. So they used a door to protect themselves and their families. The doors didn’t look like the way they do now. It was a huge stone at first. Later on the door started developing in Greece.
Explanation:hope that helps
Generally speaking, national unions differed from local unions in that national unions "<span>a)included workers from different industries", since they were able to negotiate with "larger" terms than the local, more specialized unions. </span>
I'm not sure I'd say that the Great War was more "protracted" than 19th century wars. The Great War lasted four years and some months. In the 19th century, the Civil War in the United States also lasted over four years.
The biggest difference in the Great War, early in the 20th century, was how massively destructive it was. Heavy industrialization and militarization by European nations made for a conflict that involved many nations with enormously devastating ways of inflicting damage on one another.
