Answer:
The American population was 20% of the British population.
Step-by-step explanation:
Let us call 
 the american population, 
 the British population before the migration, and 
 the population that migrated from America to Britannia. 
Now, the population 
 that migrated was 20% of the american population: 
,
and the same population 
 increase the British population by 4%: 

Combining equation (1) and (2) we get: 



Thus, the American population was 20% of the British population.
 
        
             
        
        
        
Hey hey hey I see no picc
        
             
        
        
        
Answer:
17
Step-by-step explanation:
- 38 - 21 = 17
 - 21 - 4 = 17
 - The difference between each pair of numbers above is 17, so that is the common difference.
 
I hope this helps!
 
        
                    
             
        
        
        
Answer:
6
Step-by-step explanation:
We want to expand this; (x + y)⁴
This can be written as;
(x + y)² × (x + y)²
This gives;
(x² + 2xy + y²) × (x² + 2xy + y²)
This gives;
x²(x² + 2xy + y²) + 2xy(x² + 2xy + y²) + y²(x² + 2xy + y²) = x⁴ + 2x³y + x²y² + 2x³y + 4x²y² + 2xy³ + x²y² + 2xy³ + y⁴
Simplifying gives;
x⁴ + 4x³y + 4xy³ + 6x²y² + y⁴
Thus, the coefficient of x²y² is 6