The correct answer is A the first one. 
 
        
                    
             
        
        
        
Domestic slave trade was common because it was believed to increase productivity.
        
             
        
        
        
Answer:Asia/ China
Explanation:
Centralized givernment and a corps of bureaucrats who could execute the wishes of that government and it lasted until 1911 CE
 
        
             
        
        
        
<span>The economic value of slaves in the United states exceeded the invested value of all the nations railroads factories and banks combined.</span>