Cut a piece of rectangular paper with a length of 9 cm and a width of 8 cm into the largest circle. What is the circumference of this circle?
把一张长9cm，宽8cm的长方形纸，剪成一个最大的圆．这个圆的周长是多少？
<gadget id="calculator">3.14 * 8</gadget>
<output>25.12</output>

<result>25.12</result>