cylindrical measuring cylinder has a base radius of 2 cm. When a piece of iron is taken out of the measuring cylinder, the water level drops by 5 cm. What is the volume of the piece of iron?
一个圆柱形量筒，底面半径是2厘米，把一块铁块从这个量筒里取出后，水面下降5厘米，这块铁块的体积是多少？
<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4 * 5</gadget>
<output>62.8</output>

<result>62.8</result>