Xiao Ming's garden is approximately a circle. If its diameter is 10 meters, then how many meters is its circumference?
小明家的花园近似一个圆，如果它的直径为10米，那么它的周长约是多少米．
<gadget id="calculator">3.14 * 10</gadget>
<output>31.4</output>

<result>31.4</result>