Answer:
#1. Cotton Gin
#2. A socially stratified society
#3. Harriet Tubman
#4. Mexico's desire to control the Mississippi river ( I'm not sure of this answer but i believe its right.)
#5. France
#6. Wilmont Proviso
#7. Slave states feared losing political power in the senate
#8. I'm not sure
#9. He sent federal troops to keep the peace
#10. Debates
#11. To help start the civil war
#12. Antietam
#15. Scalawags
Explanation: