A conical pile of sand has a base radius of 3 meters and a height of 0.9 meters. If each cubic meter of sand weighs 2 tons, how many tons does the pile of sand weigh?
一个圆锥形沙堆，底面半径是3米，高是0.9米，如果每立方米沙子重2吨，这堆沙子重多少吨？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

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

<gadget id="calculator">(1/3) * 3.14 * 9 * 0.9</gadget>
<output>8.478</output>

<gadget id="calculator">8.478 * 2</gadget>
<output>16.956</output>

<result>16.956</result>