The fountain in a school is a circle. If its radius is 8 meters, what is its circumference in meters?
一所学校的喷水池是一个圆形，如果它的半径为8米，那么它的周长约是多少米．
<gadget id="calculator">3.14 * 2 * 8</gadget>
<output>50.24</output>

<result>50.24</result>