First u do a squared +b squared =c squared aka pythagorean theorem then so u already have c squared so you would do 5x5=25 and 13x13=169 so then the equation would be 25+?=169 then do 169-25 which equals 144 and then do the square root of that which is 12 THE ANSWER IS 12
        
             
        
        
        
C = 2pi r 
C/2 Pi = r. 
I believe this would be the solution.
        
                    
             
        
        
        
Step-by-step explanation:
1)a) 925×4.25=3931,25
b) 1806.25:4.25=425
 I don't know second one. 
3)a 55×1.12=61.6
b) 
 
        
             
        
        
        
Answer:
10.5cm, or 4800 cubic centimeters
Step-by-step explanation:
 
        
                    
             
        
        
        
The answer might be D sir