A circular flower bed has a diameter of 6 meters, and a 1-meter-wide lawn is to be laid around it. What is the area of the lawn in square meters?
一个圆形花坛，它的直径是6米，要在它的周围铺一条1米宽的草坪，草坪的面积是多少平方米？
<gadget id="calculator">6 / 2</gadget>
<output>3</output>

<gadget id="calculator">3 + 1</gadget>
<output>4</output>

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

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

<gadget id="calculator">16 - 9</gadget>
<output>7</output>

<gadget id="calculator">3.14 * 7</gadget>
<output>21.98</output>

<result>21.98</result>