Water is needed to start farms. they could also ship goods with the river. I know my answer is not well but I hoped it helped
Answer:
1:A, as the primary sector is for the extraction of raw materials and logging includes the extraction of the raw material of wood.
2:C, as the Tertiary sector is in charge of service, downloading music is a service.
3:Shanna would be in the secondary sector as the secondary sector is in charge of manufacturing goods, vehicles, ect
I'm assuming you meant subsistence farming? If so then yes, it would be a large problem because they would then not have enough food to feed themselves.
Characteristics of a rejuvenated river include water that flows rapidly with sloping sides that create steep cuts on the valley floor.