A disc with a radius of 1 decimeter. Roll along an equilateral triangle with a side length of 6 decimeters, what is the area that the original piece passes through?
一个半径是1分米的圆片．沿着边长是6分米的等边三角形滚动一周，原片经过的面积是多少．
<gadget id="calculator">6 * 2 * 3</gadget>
<output>36</output>

<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<gadget id="calculator">36 + 12.56</gadget>
<output>48.56</output>

<result>48.56</result>