Try searching up there names and see what they all have in common
        
                    
             
        
        
        
This depends slightly on the region of Africa in question, but many of them were re-sold into slavery for other tribes in the region, while others were eventually freed. 
        
             
        
        
        
Answer:
Correct answer is b. It set up a way for all new states to be admitted to the United States. 
Explanation:
Option B is correct as this document was adopted in 1787 and according to it, it was established under which terms new countries will bee admitted in the Union.
Option A is not correct as it was established in 1818 along the 49 parallel.
Option C is also not correct as the postal service was established in 1792, although we can trace back its root to the First Continental Congress.
D is not correct as it affected all new admitted countries.
 
        
             
        
        
        
Becouse it was an immortal declaration