What is the volume of a cylinder whose base diameter and height are 8 decimeters?
底面直径和高都是8分米的圆柱的体积是多少．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16 * 8</gadget>
<output>401.92</output>

<result>401.92</result>