Build a gravel road 2 meters wide around a circular pool with a diameter of 6 meters. What is the area of this gravel road in square meters?
在一个直径是6米的圆形水池周围，修一条2米宽的石子路．这条石子路的面积是多少平方米？
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 + 2</gadget>
<output>5</output>

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

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

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

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

<result>50.24</result>