There is a circular flower bed with a diameter of 8m and a circular path with a width of 1m outside. What is the area of this circular path in m**2?
有一个直径是8m的圆形花坛，外面有一条宽1m的环形小路，这条环形小路的面积是多少m**2？
<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">3.14 * 25</gadget>
<output>78.5</output>

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

<gadget id="calculator">3.14 * 16</gadget>
<output>50.24</output>

<gadget id="calculator">78.5 - 50.24</gadget>
<output>28.26</output>

<result>28.26</result>