When drawing a circle, the distance between the legs of the compass is 2 cm, what is the circumference of the circle drawn in cm?
画圆时，圆规两脚叉开的距离是2cm，画出的圆的周长是多少cm．
<gadget id="calculator">3.14 * 2 * 2</gadget>
<output>12.56</output>

<result>12.56</result>