The height of the water surface in a cylindrical bucket is 12 cm, and a conical billet (submerged in water) is placed in the bucket. At this time, the height of the water surface rises to 15 cm. If the diameter of the bottom surface of the bucket is 20 cm. What is the volume of this billet?
一个圆柱形水桶里水面的高度是12厘米，在水桶里放入一个圆锥形钢坯(浸没水中)，这时水面的高度上升至15厘米，如果水桶的底面直径是20厘米．这个钢坯的体积是多少？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">15 - 12</gadget>
<output>3</output>

<gadget id="calculator">3.14 * 100 * 3</gadget>
<output>942</output>

<result>942</result>