Find the circumference of a circle if the area is 300 square centimeters.
a. 56.25 cmb. 9.77 cmc. 61.38 cmd. 84.74 cm

The answer is:  [C]:  61.38 cm  .
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Note:  A = ²

300 = (3.14) * r² ;
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Divide each side by "3.14" ;

r² = 300/3.14 ; 

r² =  95.5414012738853503 ;

√r² = √(95.5414012738853503) ;

r = 9.7745281867661188048

Circumference, "C" =  * d ;  (d = diameter = 2*r);
 
C = 2**r ;

C = 2*(3.14)*(9.7745281867661188048)

C = 61.384037012891226094144 ; which rounds to answer choice: 
                                                             [C]:  61.38 cm  .
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The answer is 225 miles per 4.5 hours. hope this ; )