Answer:
C. The awareness of impending death came about slowly, subtly
Explanation:
According to the given excerpt, the comment from Dickinson about expecting death in the line “since then — tis centuries — and yet/ feels shorter that the day/ I first surmised the horses head/ were toward eternity" is the awareness of impending death came about slowly, subtly. 
This is because he slowly realizes as he feels shorter that day and finding out that the horses egad was toward eternity. 
 
        
             
        
        
        
Answer:
the passengers and Twain perceive the river in very different ways.
Explanation:
Right after it, Twain continues: <em>"Now when I had mastered the language of this water and had come to know every trifling feature that bordered the great river as familiarly as I knew the letters of the alphabet, I had made a valuable acquisition."</em>
He sees the river in a different way and much is to be told from what the river shows, it seems, but passengers are not able to see what he sees because they do not share the same knowledge.
 
        
                    
             
        
        
        
How they are going to: achieve higher goals.
:)
 
        
                    
             
        
        
        
Answer:
a
Explanation:
 The description emphasizes the differences between the cultures.
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