A conical heap of wheat, put this heap of wheat into a cylindrical granary just enough to fill it up. The diameter of the bottom of the granary is 4 meters and the height is 3 meters. What is the volume of this conical wheat heap in cubic meters?
一个圆锥形小麦堆，把这堆小麦装进圆柱形粮屯正好装满，粮屯的底面直径是4米，高3米，这个圆锥形小麦堆的体积是多少立方米？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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

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

<gadget id="calculator">(1/3) * 3.14 * 4 * 3</gadget>
<output>12.56</output>

<result>12.56</result>