A cone-shaped sand pile has a base diameter of 10 meters and a height of 2.1 meters. If each cubic meter of sand weighs about 1.8 tons, how many tons is this pile of sand?
一个圆锥形的沙堆，底面直径是10米，高是2.1米．如果每立方米沙约重1.8吨，那么这堆沙大约有多少吨？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">(1/3) * 3.14 * 25 * 2.1</gadget>
<output>54.95</output>

<gadget id="calculator">54.95 * 1.8</gadget>
<output>98.91</output>

<result>98.91</result>