The circumference of a circular cistern is 125.6 meters, how many square meters does this circular cistern occupy?
一个圆形蓄水池的周长是125.6米，这个圆形蓄水池的占地面积是多少平方米？
<gadget id="calculator">125.6 / 3.14 / 2</gadget>
<output>20</output>

<gadget id="calculator">20 ** 2</gadget>
<output>400</output>

<gadget id="calculator">3.14 * 400</gadget>
<output>1_256</output>

<result>1_256</result>