The diameter of the front wheel of a road roller is 1.5 meters, the wheel width is 4 meters, and the front wheel rolls once, what is the area of the road being rolled?
一台压路机前轮直径1.5米，轮宽4米，前轮滚动一周，压路的面积是多少．
<gadget id="calculator">3.14 * 1.5 * 4</gadget>
<output>18.84</output>

<result>18.84</result>