Answer:
The class had studied the planets before the solar system
Explanation:
 
        
             
        
        
        
Calm. That is the word I came up with. It was hard to know what you meant though.
        
             
        
        
        
D He performs badly, compared to Algernon
        
             
        
        
        
As per convention:
- the angle at A is named A, the angle at B is named B, and the angle at C is named C
- the side of leght a is the side opposed to A, the side of length b is opposed to B, and the side of length c is opposed to C.
Now just state the law of cosines:
c^2 = a^2 + b^2 - 2ab cos(C)
Also, a^2 = c^2 + b^2 - 2bc cos (A)
And, b^2 = a^2 + c^2 - 2ac cos (B)
        
             
        
        
        
The answer is E.
Hope it helps!