The radius of a circular plate is 8 cm, what is the circumference of the circular plate?
一个圆形盘子的半径是8cm，这个圆形盘子的周长是多少？
<gadget id="calculator">2 * 8</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16</gadget>
<output>50.24</output>

<result>50.24</result>