There is a circular fountain with a radius of 2 meters in the garden in the middle of the street. Now a path with a width of 1 meter is to be built along the perimeter of the fountain. What is the area of this path in square meters?
街心花园有一个半径是2米的圆形喷水池，现要沿喷水池的周围修一条宽1米的小路．这条小路的面积是多少平方米？
<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

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

<gadget id="calculator">9 - 4</gadget>
<output>5</output>

<gadget id="calculator">3.14 * 5</gadget>
<output>15.7</output>

<result>15.7</result>