The St. Lawrence River and the Columbia River border Canada and the United States.
Answer:
Northern Africa.
Explanation:
Northern Africa is the region where the smallest portion of the population in slums. North African countries are making progress in reducing slum areas. Most of the countries are introducing new policies for housing and urban development. The flourishing of economic condition in northern Africa countries has helped people engaging in getting employment. The new industrial area, agricultural and crafts towns supported people who moved out of their rural areas in search of job opportunities.
I don't know the answer but it affected it because now the people who are settling in that area to not cross because they have to make their crops and the railroad being in the way of that is stressful because of the noise and because it's right in the middle of where they're settling