Xiao Ming took out a rockery completely submerged in water from a cylindrical fish tank with a bottom diameter of 20cm (internal measurement). The water surface dropped from 32cm to 26cm. What is the volume of this rockery?
小明从一个底面直径是20cm(内部测量)的圆柱形鱼缸取出一个完全浸入在水中的假山，水面由32cm降到26cm，这个假山的体积是多少？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

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

<gadget id="calculator">32 - 26</gadget>
<output>6</output>

<gadget id="calculator">3.14 * 100 * 6</gadget>
<output>1_884</output>

<result>1_884</result>