Nomads had a great impact on the song dynasty, threatening borders and then conquering china in the 1120s, founding the jin empire, while the song dynasty continued to rule china for another 150 years.

southern; northern
eastern; western
northern; southern
western; eastern

northern; southern

Explanation:

Nomads had a great impact over China. The Jurchen were a tribe that originated from Manchuria but conquered a part of China, especially the Northern part. They invaded parts of Northern China in 1126 CE. The relationship between Jin dynasty and Song China them remained friendly, they even signed a peace treaty in 1142 CE.

the right answer is the third one: turnpikes went short distances to connect markets. turnpikes, also known as toll roads, were very important for trade and transportation (of people, goods and products) in the 19th century, coinciding with the expansion towards the west. they contributed significantly to the economic development of the united states.