Answer:

Step-by-step explanation:
The formula for the area of a circle is  , r is your radius, A is your area, and π is pi (3.1415...). You plug in your radius, or 5 into r, square it, 25, and multiply it by pi. You may be asked to use a certain number of digits of pi, and in that case you multiply for example 3.14 by 25, however
, r is your radius, A is your area, and π is pi (3.1415...). You plug in your radius, or 5 into r, square it, 25, and multiply it by pi. You may be asked to use a certain number of digits of pi, and in that case you multiply for example 3.14 by 25, however  is the exact answer.
 is the exact answer.
 
        
             
        
        
        
If the Diameter Is 4 inches then the radius will be 2 inches!
Hope I Helped!
        
                    
             
        
        
        
The answer would be=22.9n
        
             
        
        
        
Really, 

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