There is a cylindrical glass jar with a diameter of 20 cm on the inner bottom surface, which holds a part of water and puts a stone in it. When the stone is completely submerged in the water, the water level rises by 3 cm. What is the volume of the stone?
有一个圆柱体玻璃缸，内底面直径是20厘米，盛一部分水，放入一块石头．当石头完全沉没水中之后，水面上升3厘米．石头的体积是多少？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

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

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

<result>942</result>