A cuboid water tank measures 5 decimeters in length, 4 decimeters in width, and 1.8 decimeters in depth. When an irregular stone is submerged in the water, the water rises by 2.5 centimeters. What is the volume of the stone in cubic decimeters?
一个长方体水箱从里面量长5分米，宽4分米，水深1.8分米，当一个不规则的石块浸没水中时，这时水上升2.5厘米，这个石块的体积是多少立方分米？
<gadget id="calculator">2.5 / 10</gadget>
<output>0.25</output>

<gadget id="calculator">5 * 4 * 0.25</gadget>
<output>5</output>

<result>5</result>