d=12 cm, h=20 cm, find the volume of this cylinder.
d=12厘米，h=20厘米，求这个圆柱的体积．
<gadget id="calculator">12 / 2</gadget>
<output>6</output>

<gadget id="calculator">6 ** 2</gadget>
<output>36</output>

<gadget id="calculator">3.14 * 36 * 20</gadget>
<output>2_260.8</output>

<result>2_260.8</result>