In a cylindrical bucket with a bottom radius of 20 cm, a steel cylinder with a diameter of 10 cm is submerged in water. When it is taken out, the water level drops 2 cm. How many centimeters is this piece of steel?
在一只底面半径为20厘米圆柱形水桶里有一个直径为10厘米的圆柱体钢材浸没于水中，当取出它后，水面下降2厘米．这段钢长多少厘米？
<gadget id="calculator">20 ** 2</gadget>
<output>400</output>

<gadget id="calculator">3.14 * 400 * 2</gadget>
<output>2_512</output>

<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25</gadget>
<output>78.5</output>

<gadget id="calculator">2_512 / 78.5</gadget>
<output>32</output>

<result>32</result>