A yurt with a circular base has a circumference of 28.26m. How many square meters does it occupy?
一个底面是圆形的蒙古包，量得它的底面周长是28.26m，它的占地面积是多少平方米？
<gadget id="calculator">2 * 3.14</gadget>
<output>6.28</output>

<gadget id="calculator">28.26 / 6.28</gadget>
<output>4.5</output>

<gadget id="calculator">4.5 ** 2</gadget>
<output>20.25</output>

<gadget id="calculator">3.14 * 20.25</gadget>
<output>63.585</output>

<result>63.585</result>