Cast a piece of cylindrical iron with a bottom radius of 2 decimeters and a height of 8 decimeters into a square steel with a side length of 2 decimeters in cross section. What is the length of this square steel?
将一段底面半径为2分米，高8分米的圆柱形铁块，铸造成一个横截面边长为2分米的方钢，这个方钢的长是多少分米？
<gadget id="calculator">2 ** 2</gadget>
<output>4</output>

<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">8 / 4</gadget>
<output>2</output>

<gadget id="calculator">3.14 * 4 * 2</gadget>
<output>25.12</output>

<result>25.12</result>