The bottom surface is 4 cm in diameter and 12 cm high. Find the volume of the cylinder.
底面直径4厘米，高12厘米．求圆柱的体积．
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

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

<gadget id="calculator">3.14 * 4 * 12</gadget>
<output>150.72</output>

<result>150.72</result>