The length of an approximate rectangle formed by cutting a circle is 6.28 centimeters, what is the radius of this circle in centimeters.
由一个圆剪拼成的近似长方形的长是6.28厘米，这个圆的半径是多少厘米．
<gadget id="calculator">6.28 * 2</gadget>
<output>12.56</output>

<gadget id="calculator">2 * 3.14</gadget>
<output>6.28</output>

<gadget id="calculator">12.56 / 6.28</gadget>
<output>2</output>

<result>2</result>