They killed them for food.The Lakota Tribe killed buffalo,but worshiped them and made sure to use every single bit of it.They only kille dit if they really needed it.
Since you're in a rush, the shortest answer would be that it is D., William Seward, whom decided to buy Alaska.
- proved that articles of confederation too weak because they couldn't collect taxes to raise army
- people began calling for stronger govt and Constitution was created
