Given that the width of a ring is 2 cm, how much is the circumference of the larger circle of the ring longer than the smaller circumference in cm?
已知一圆环宽度为2cm，则圆环大圆周长比小圆周长多少cm．
<gadget id="calculator">2 * 3.14 * 2</gadget>
<output>12.56</output>

<result>12.56</result>