An automatic rotary sprinkler has a range of 12 meters, what is the area it can irrigate.
一个自动旋转喷灌装置射程是12米，它能灌溉的面积是多少．
<gadget id="calculator">12 ** 2</gadget>
<output>144</output>

<gadget id="calculator">3.14 * 144</gadget>
<output>452.16</output>

<result>452.16</result>