Demand for crops fell after World War I
<span>Harriet Tubman's primary role in the effort to abolish slavery was that he established the "Underground Railroad" (not an actual railroad), which helped slaves escape from the South to freedom. </span>
Advantage:
They were fighting on their home country. (they didn't have to travel overseas)
Britain was fighting France at the same time as they were fighting the US
Disadvantage:
They didn't have a trained army.
They didn't have much $.
E: both B and D. The automobile and the mass assembly line
