Draw the largest circle inside the square, if the circumference of this circle is 12.56 cm, what is the area of the square in square centimeters
在正方形内画一个最大的圆，若此圆周长是12.56厘米，则正方形面积是多少平方厘米
<gadget id="calculator">12.56 / 3.14</gadget>
<output>4</output>

<gadget id="calculator">4 * 4</gadget>
<output>16</output>

<result>16</result>