Based on the other answer, I'm guessing that it was A. Russians were likely to reject pure Marxism because Marx was a German. (I'll update it when I know for sure.)
About 35 years. Genghis Khan created the Mongol empire in 1206. By the 1230s Batu Khan invaded Russian and Bulgarian lands. In 1241 at the battle of Mohi Batu Khan defeater a combined German, Polish and Hungarian army. Further expansion ceased do to the death of Ogedei Khan. Batu Khans attention was turned to succession instead of invading Western Europe.
During the antebellum era, both the North and the South have been producing cotton and textiles. However, because the North has far more advantages than the south in terms of technological advancements, the North was able to produce more products by the end of the era such as guns, crops, machine parts and more.