Submerge a cube of iron with a side length of 20 cm in a rectangular parallelepiped glass jar with a length of 50 cm, a width of 40 cm, and a height of 35 cm. When the iron block is taken out, how many centimeters will the water level in the jar drop?
把棱长20厘米的正方体铁块浸没在一个长50厘米、宽40厘米、高35厘米的长方体玻璃缸中，当拿出铁块后，缸里的水面下降多少厘米．
<gadget id="calculator">50 * 40</gadget>
<output>2_000</output>

<gadget id="calculator">20 / 2_000</gadget>
<output>1/100 = around 0.01</output>

<gadget id="calculator">20 * 20 * (1/100)</gadget>
<output>4</output>

<result>4</result>