What allowed the Vikings to be so successful in plundering(attacks and theft) Europe?

european feudalism was a combination of legal and military customs in medieval europe that flourished between the 9th and 15th centuries. broadly defined, it was a way of structuring society around relationships derived from the holding of land in exchange for service or labour.

japanese feudalism. the era of feudalism in japan took place from the 12th through 19th centuries. during that period local rulers, either powerful families or military warlords, dominated the land, while the emperor was merely a figurehead and not a significant political presence.

two jet streams that directly affect the formation of weather in the continental part are a polar jet and a subtropical jet. they are responsible for the transportation of weather systems, which directly affect people. the polar front is the boundary between cold air from the north pole and warmer equatorial air. both the polar jet and the subtropical jet blow from the west to the east, and follow the boundary between cold and warm air.

the strongest jet streams are polar jets, while subtropical jets are somewhat weaker.

the right answer is c. the polar jet stream is generaly stronger than the subtropical jet stream.