Why does trade often result in cultural diffusion ?

Look at the map of cities in the united states at the turn of the twentish century what impact did railroads have on cities across the united states at the turn of the twentish century

The sahel is located on the edge of the sahara desert. a. north b. west c. south d. east

56: 58 the assembly line was a system through which items were mass-produced in a flow.