A circular flower bed has a circumference of 9.42 meters, and a circular railing is enclosed 0.5 meters away from the edge of the flower bed. What is the length of the railing in meters?
一个圆形花坛，周长为9.42米，在离开花坛边0.5米的外面围一个圆形栏杆，则栏杆的长约为多少米．
<gadget id="calculator">9.42 / 3.14 / 2</gadget>
<output>1.5</output>

<gadget id="calculator">1.5 + 0.5</gadget>
<output>2</output>

<gadget id="calculator">3.14 * 2 * 2</gadget>
<output>12.56</output>

<result>12.56</result>