A flower bed has a diameter of 20 meters, and there is a circular path with a width of 1 meter around it. What is the area of the path in square meters?
一个花坛，直径20米，在它的周围有一条宽1米的环形小路，小路的面积是多少平方米？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 + 1</gadget>
<output>11</output>

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

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">121 - 100</gadget>
<output>21</output>

<gadget id="calculator">3.14 * 21</gadget>
<output>65.94</output>

<result>65.94</result>