Use a rectangular iron sheet with a length of 28.26 decimeters and a width of 15.7 decimeters to roll into a cylindrical barrel (without joints). At least one piece of square iron sheet with a side length of the same length can be cut to process the bottom of a barrel with the largest volume without a cover. ．
用一块长28.26分米，宽15.7分米的长方形铁皮卷成一个圆柱形桶(不留接头)，至少要剪一块边长是多少的正方形铁皮就可以加工成一个无盖容积最大的桶的底．
<gadget id="calculator">28.26 / 3.14</gadget>
<output>9</output>

<result>9</result>