25.12 meters long iron wire encloses a circle, what is the area of the circle in square meters?
把25.12米长的铁丝围成一个圆，这个圆的面积为多少平方米．
<gadget id="calculator">25.12 / 3.14 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16</gadget>
<output>50.24</output>

<result>50.24</result>