A conical grain mound has a base radius of 2m and a height of 3m. If each cubic meter of grain weighs about 1.5 tons, how many tons does this pile of grain weigh?
一个圆锥形谷堆，底面半径是2m，高3m．如果每立方米谷约重1.5吨，这堆谷约重多少吨？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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

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

<gadget id="calculator">12.56 * 1.5</gadget>
<output>18.84</output>

<result>18.84</result>