A 1-meter-wide gravel road is paved around a circular flower bed with a diameter of 6 meters. What is the area of the gravel road in square meters?
沿着直径是6米的圆形花坛周围铺1米宽的石子路，石子路的面积是多少平方米？
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

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