There is a ring with an inner diameter of 6 cm and an outer circumference of 25.12 cm. What is the area of the ring?
有一个圆环，内圆直径是6厘米，外圆周长是25.12厘米，这个圆环的面积是多少？
<gadget id="calculator">25.12 / 3.14 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">16 - 9</gadget>
<output>7</output>

<gadget id="calculator">3.14 * 7</gadget>
<output>21.98</output>

<result>21.98</result>