The diameter of a wheel is 50 cm, and the wheel rolls 10 times, how many cm does it move forward?
一个车轮直径是50cm，车轮滚动10圈，前进了多少cm．
<gadget id="calculator">3.14 * 50 * 10</gadget>
<output>1_570</output>

<result>1_570</result>