There is a circular flower bed in the middle of a crossroad. The diameter of the flower bed is 30 meters. How many square meters does this flower bed occupy?
一个十字路口的中间有个圆形花坛，花坛的直径是30米，这个花坛的占地面积是多少平方米？
<gadget id="calculator">30 / 2</gadget>
<output>15</output>

<gadget id="calculator">15 ** 2</gadget>
<output>225</output>

<gadget id="calculator">3.14 * 225</gadget>
<output>706.5</output>

<result>706.5</result>