Draw a circle with a circumference of 15.7 centimeters, how many centimeters should the two feet of the compass measure on the ruler.
画一个周长是15.7厘米的圆，圆规的两脚应在直尺上量取多少厘米的距离．
<gadget id="calculator">2 * 3.14</gadget>
<output>6.28</output>

<gadget id="calculator">15.7 / 6.28</gadget>
<output>2.5</output>

<result>2.5</result>