The circumference of a circular pool is 12.56 meters. What is its area in square meters?
一个圆形水池的周长是12.56米．它的面积是多少平方米？
<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>