The area occupied by the sand pile on the ground is exactly a circle, and the length of its circumference is measured to be 12.56m, so what is the bottom area of the sand pile in m**2?
砂子堆在地面上占地正好是圆形，量出它一周的长度是12.56m，那么砂子堆底面积是多少m**2？
<gadget id="calculator">12.56 / 3.14 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<result>12.56</result>