The radius of a circular pond is 15 meters, what is the circumference of the circular pond in meters?
一个圆形池塘的半径是15米，这个圆形池塘的周长是多少米？
<gadget id="calculator">3.14 * 15 * 2</gadget>
<output>94.2</output>

<result>94.2</result>