The XYZ affair led to a period of anti-French sentiment in the United States, which was problematic as the French has been the key ally during the American revolution some 20 years before and was one of the primary reasons the United States was able to defeat Great Britain.
However, over those 20 years, France had undergone a revolution of their own and the United States decided to remain neutral in France's war against Great Britain.
The Black Death killed 38 million people, it was a terrible illness which spread rapidly.
The Great Schism was in 1054 and the Christian church broke up into two sections, which essentially divided the Church with two popes.
I would say that trade would be "believed to travel to Europe because of this", because it would not really fit anywhere else.
Now, I'm not two sure on the last one but the Hundred Years War was where King Edward the III of England thought that he should be the king of France, so there was a very long battle between the two. I would say the Hundred Years War would be started by division of the heir to the throne of England, and France and Italy did not agree who was to be pope. Since the Hundred Years War had really nothing to do with Italy.
B:
Agriculture, water projects, shipyards all offered steady work to people driven out of the plains states.
The main reason why the Framers of the Constitution included the amendment process was because "A.)They wanted to provide a way to change the Constitution as the country changed," since they new that a "rigid" document would lead to disaster.