A graduated cylinder with a base radius of 5 cm contains water at a height of 8 cm. A piece of iron is placed in a measuring cylinder, the water level rises to 10 cm, find the volume of the piece of iron.
在底面半径是5厘米的量筒里面装有8厘米高的水．把一块铁块放入量筒中，水面上升到10厘米，求这块铁块的体积．
<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">10 - 8</gadget>
<output>2</output>

<gadget id="calculator">3.14 * 25 * 2</gadget>
<output>157</output>

<result>157</result>