I think that statement is true.
There are indeed many sources of air pollutants in both urban and rural settings.
In urban settings, the most common sources of air pollutants came from vehicle's emission.
Meanwhile, in rural settings, the most common pollutants came from mining process or factory waste.
        
             
        
        
        
Letter A is the correct answer. 
In the year of 1848, about 300 people gathered together to fight for the social, religious, and civil rights of women in the United States. Seneca Falls Convention was the first women's right convention in the United States, even though 15 years earlier women's rights advocates had already started speaking out on moral and political issues and fighting against gender discrimination that prevented married women from owning property.  
 
        
             
        
        
        
I believe the year in question is not 1970 but 1790. 
The answer to the question is South Carolina. Given its small size compared to the other states they had the huge number of slaves about 65%. The 65% were African-American slaves. The slaves population in South Carolina grew in connection to their rice culture success.  
        
             
        
        
        
Answer: Checks and Balances System
The civil service system contributes to the well-functioning of the government, but does nothing to prevent abuses of power.
The spoils system is a practice where the winning party in an election gives civil service jobs to its supporters. This undermines the prevention of the arbitrary use of power.
The separation of powers contributes to limit the power one section of the government has, but it does not necessarily forge consensus.
<em>The checks and balances system, however, prevents the arbitrary use of power by allowing all powers to check on each other. It also fosters cooperation on divisive issues.
</em>
 
        
             
        
        
        
His unknown secret weapon was disease.
When Cortez and his army invaded aztecs, a couple of his men were infected with smallpox.
Since the aztecs did not possess any immunity for it, the majority of their people were weakened by the disease, which make it easier for cortez army to conquer their region.