Build a 2-meter-wide path outside a circular flower bed with a diameter of 10 meters, and walk around the outer circle, how many meters to walk.
在直径10米的圆形花坛外修一条2米宽的小路，绕外圈走一圈，要走多少米．
<gadget id="calculator">10 + 2 + 2</gadget>
<output>14</output>

<gadget id="calculator">3.14 * 14</gadget>
<output>43.96</output>

<result>43.96</result>