Put a cube iron block with a side length of 2 decimeters in a cuboid glass tank with a length of 80 cm and a width of 40 cm. If the iron block is completely submerged in the water, how many centimeters will the water level in the tank rise?
在一个长80厘米，宽40厘米的长方体玻璃缸里放入一个棱长为2分米的正方体铁块，铁块完全没入水中，水缸里面的水面会上升多少厘米？
<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">20 * 20 * 20</gadget>
<output>8_000</output>

<gadget id="calculator">8_000 / 80 / 40</gadget>
<output>5/2 = around 2.5</output>

<result>5/2 = around 2.5</result>