Answer:
The base unit of time in the International System of Units (SI) and by extension most of the Western world, is the second, defined as about 9 billion oscillations of the caesium atom. The exact modern definition, from the National Institute of Standards and Technology is: "The second, symbol s, is the SI unit of time.
Explanation:
 
        
             
        
        
        
<u>Answer:</u> Slaves or Gold
<u>Reasoning:</u> The yellow line is Africa's line, marked as "Slaves, gold"
 
        
                    
             
        
        
        
Answer:
trade at Songhai was done by land while trade in Mogadishu was done by boats
Explanation:
Songhai participated in the Trans Saharan which mainly took place on land across the Saharan desert  while Mogadishu used boats because it was located along the coast and they took part in the East African coastal trade.
 
        
             
        
        
        
Between the given period, the US increased in size having spread towards the west, while in the meantime fighting for human rights and freeing the slaves.
        
             
        
        
        
Answer:
Using art from ancient Roman buildings to determine which emperor built the Colosseum 
Explanation:
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