Put an iron ball that can be completely submerged in water into a cylindrical water-filled cup with a circumference of 31.4 cm at the bottom.
底面周长31.4厘米的圆柱形盛水杯子中放入一个能全部浸没水中的铁球，水面高6厘米，取出铁球后水面下降4厘米，这个铁球的体积是多少立方厘米？
<gadget id="calculator">31.4 / 3.14 / 2</gadget>
<output>5</output>

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

<gadget id="calculator">3.14 * 25 * 4</gadget>
<output>314</output>

<result>314</result>