The radius of the large circle is 3 cm greater than the radius of the small circle, and the circumference of the large circle is greater than the circumference of the small circle by how many centimeters.
大圆半径比小圆半径多3厘米，大圆周长比小圆周长多多少厘米．
<gadget id="calculator">2 * 3.14 * 3</gadget>
<output>18.84</output>

<result>18.84</result>