A cuboid glass tank is 40 cm long and 25 cm wide when measured from the inside, and the water depth in the tank is 10 cm. After a stone is immersed in water, the water level rises to 12 cm, find the volume of the stone.
一个长方体玻璃缸，从里面量长40厘米，宽25厘米，缸内水深10厘米．把一块石头浸入水中后，水面升到12厘米，求石块的体积．
<gadget id="calculator">12 - 10</gadget>
<output>2</output>

<gadget id="calculator">40 * 25 * 2</gadget>
<output>2_000</output>

<result>2_000</result>