There is a circular flower bed with a diameter of 8 meters in the center of Xingfu Park. Now it is going to pave a cobblestone path with a width of 1 meter around the flower bed. How many square meters is the area of this cobblestone path?
幸福公园中心有一个直径8米的圆形花坛，现准备绕花坛四周铺一条宽1米的鹅卵石小路，这条鹅卵石小路的面积有多少平方米？
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

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

<gadget id="calculator">25 - 16</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9</gadget>
<output>28.26</output>

<result>28.26</result>