There is a circular fountain in Zhongshan Park with a diameter of 18 meters. A 2-meter-wide gravel path is paved around it. What is the area of this path in square meters?
中山公园有一个圆形喷泉，直径是18米，在它的周围铺一条2米宽的石子小路，这条小路的面积是多少平方米？
<gadget id="calculator">18 / 2</gadget>
<output>9</output>

<gadget id="calculator">9 + 2</gadget>
<output>11</output>

<gadget id="calculator">11 ** 2</gadget>
<output>121</output>

<gadget id="calculator">9 ** 2</gadget>
<output>81</output>

<gadget id="calculator">121 - 81</gadget>
<output>40</output>

<gadget id="calculator">3.14 * 40</gadget>
<output>125.6</output>

<result>125.6</result>