21.) is clue
I don't know the others I'm sorry...
        
             
        
        
        
Hope this helps with the answer to your question :)
 
        
        
        
Answer:
   C = 18
Step-by-step explanation:
Put the numbers in place of their symbols and do the arithmetic. The diagram is showing you r = 3.
   C = 2πr
   C = 2(3)(3) . . . . . using 3 for π, as directed
   C = 18
 
        
                    
             
        
        
        
Answer:
none of them its <
Step-by-step explanation: