Well the Mongol conquests united large portions of land that had previously not been together. As well, the Mongols facilitated a lot of trade by introducing things from all over the empire. For example, they brought a lot of Middle Eastern scientists and artists into the Middle East, which promoted the exchange of culture.
One significant indication that the European feudal system was effective was that "<span>Similar
systems developed in China and Japan" although it should be noted that
this isn't enough evidence to prove that it was economically successful.Hope this helps!!!</span>
I belive the answer would be B ( B. A National Guard unit is sent to help a state prepare for natural disasters. )
:) sorry if I'm wrong, have and amazing day mate
Starting in 1939, any nation fighting in World War II could purchase goods and arms in the United States under the Lend - Lease program.