36 children form a circle to play games. The distance between every two adjacent children is 2 meters. What is the circumference of this circle in meters?
36个小朋友围成一个圆圈做游戏，每相邻两个小朋友之间都是2米，这个圆圈的周长是多少米？
<gadget id="calculator">36 * 2</gadget>
<output>72</output>

<result>72</result>