Answer:
idk i kinda forgot what was the answer let me go check
 
        
                    
             
        
        
        
No, I just took the test, 
The answer would be 
C. P(solid)22
        
                    
             
        
        
        
Y= x + 3
1. Find the gradient(slope) 
1 - 7 / - 2 - 4
=1
2. Find the y. Intercept ( c )
 Y = x + c 
Replace by any of the two coordinates given (4 , 7 )
7 = 4 + c
C= 3
Equation => Y = x + 3
        
             
        
        
        
The answer is B. That is not a valid way to sample as it is not randomly selected.
        
             
        
        
        
16m^4 - n^4 
= (4m^2 + n^2)(4m^2 - n^2)
= (4m^2 + n^2) (2m + n)(2m - n)