The diameter of a circular flower bed is 4 meters, and a 2-meter-wide path is paved around it. What is the area of this path in square meters?
一个圆形花坛的直径是4米，在它的四周铺一条2米宽的小路，这条小路面积是多少平方米？
<gadget id="calculator">4 / 2</gadget>
<output>2</output>

<gadget id="calculator">2 + 2</gadget>
<output>4</output>

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

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

<gadget id="calculator">16 - 4</gadget>
<output>12</output>

<gadget id="calculator">3.14 * 12</gadget>
<output>37.68</output>

<result>37.68</result>