A metal cone with a base diameter of 40 cm is immersed in a cylindrical glass with a base diameter of 80 cm. At this time, the water level in the glass is 2 cm higher than before. Find the height of the metal cone.
把一个底面直径为40厘米的金属圆锥浸在底面直径为80厘米圆柱形玻璃杯里，这时杯中水面比原来升高了2厘米，求金属圆锥的高．
<gadget id="calculator">80 / 2</gadget>
<output>40</output>

<gadget id="calculator">40 ** 2</gadget>
<output>1_600</output>

<gadget id="calculator">3.14 * 1_600 * 2</gadget>
<output>10_048</output>

<gadget id="calculator">40 / 2</gadget>
<output>20</output>

<gadget id="calculator">20 ** 2</gadget>
<output>400</output>

<gadget id="calculator">3.14 * 400</gadget>
<output>1_256</output>

<gadget id="calculator">3 / 1_256</gadget>
<output>3/1_256 = around 0.002389</output>

<gadget id="calculator">10_048 * (3/1_256)</gadget>
<output>24</output>

<result>24</result>