Answer:
4.Assistance from other European powers.
Technological progress is defined as D) an improvement in the efficiency with which an economy uses its resources and factors of production to produce increased output.
Answer:
Because the North had more factories
it could
produce more weapons than the South could.
A theory is a hypothesis that is proved to be true through rigorous scientific methods of verfiication, mathematical and scientific arguments. Theories escalate into laws more when found out to be a natural fact. In this case, the answer would have to be A.