A cuboid fish tank has a length of 80 cm, a width of 50 cm, and a water storage depth of 20 cm. Now put a small rockery into the water completely, and the water level has risen by 2 cm. Find the volume of this small rockery?
一个长方体鱼缸，长是80厘米，宽是50厘米，蓄水深20厘米，现将一个小假山完全放入水中，此时水面上升了2厘米．求这个小假山的体积？
<gadget id="calculator">80 * 50 * 2</gadget>
<output>8_000</output>

<result>8_000</result>