The answer would be d. (1,3.5)
you would use the midpoint formula that is attached below. 
 
        
        
        
Answer:
a
Step-by-step explanation:
ii am right 
 
        
                    
             
        
        
        
Answer:
780
Step-by-step explanation:
So when you're adding consecutive numbers like this. 1+2+3...+39. You add 39 and 1. This is 40. 2+38 is 40. This is a pattern. Now, we do 40 multiplied by 39 and this will give you the number 1620. After this you would have to divide this product by 2. The answer will soon be 780.
 
        
             
        
        
        
Answer: D 
Step-by-step explanation: I think
 
        
             
        
        
        
25/6 converts to 4 1/6 so 
4 1/6 x 2 = 8 1/3 
8 1/3 is your answer :)