How many square meters does a circular sand pile with a bottom circumference of 47.1 meters cover?
一个底面周长47.1米的圆形沙堆，占地面积多少平方米？
<gadget id="calculator">47.1 / 3.14 / 2</gadget>
<output>7.5</output>

<gadget id="calculator">7.5 ** 2</gadget>
<output>56.25</output>

<gadget id="calculator">3.14 * 56.25</gadget>
<output>176.625</output>

<result>176.625</result>