A wire can form an equilateral triangle with a side length of 6.28 cm. If it is straightened to form a circle, what is the area of the circle in square centimeters?
一根铁丝可以围成一个边长为6.28厘米的等边三角形，如果把它拉直围成一个圆，则这个圆的面积是多少平方厘米．
<gadget id="calculator">6.28 * 3</gadget>
<output>18.84</output>

<gadget id="calculator">18.84 / 3.14</gadget>
<output>6</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9</gadget>
<output>28.26</output>

<result>28.26</result>