The correct answers are
a) 40%
b) 30%
        
                    
             
        
        
        
it would be c 9/25 and 9/25
 
        
             
        
        
        
Circumference for the circle is B
        
                    
             
        
        
        
Answer:
option 3
Step-by-step explanation:
all other angles are  interior and exterior
 
        
                    
             
        
        
        
We find the first differences between terms: 
7-4=3; 12-7=5; 19-12=7; 28-19=9. 
Since these are different, this is not linear. 
We now find the second differences: 
5-3=2; 7-5=2; 9-7=2. Then:
Since these are the same, this sequence is quadratic. 
We use (1/2a)n², where a is the second difference: 
(1/2*2)n²=1n². 
We now use the term number of each term for n: 
4 is the 1st term; 1*1²=1. 
7 is the 2nd term; 1*2²=4. 
12 is the 3rd term; 1*3²=9. 
19 is the 4th term; 1*4²=16. 
28 is the 5th term: 1*5²=25. 
Now we find the difference between the actual terms of the sequence and the numbers we just found: 
4-1=3; 7-4=3; 12-9=3; 19-16=3; 28-25=3. 
Since this is constant, the sequence is in the form (1/2a)n²+d; 
in our case, 1n²+d, and since d=3, 1n²+3.
The correct answer is n²+3