If the distance between the feet of the compass is 3 cm, what is the circumference of the circle drawn with it?
圆规两脚间的距离是3厘米，用它画成的圆的周长是多少厘米．
<gadget id="calculator">2 * 3.14 * 3</gadget>
<output>18.84</output>

<result>18.84</result>