When drawing a circle, spread the legs of the compass 6 cm apart. What is the circumference of the circle in cm?
在画圆时把圆规的两脚张开6厘米，这个圆的周长是多少厘米．
<gadget id="calculator">2 * 3.14 * 6</gadget>
<output>37.68</output>

<result>37.68</result>