The front roller of a road roller is 2 meters long and 1.5 meters in diameter, and it can make 50 revolutions in one minute. What is the rolling area in one minute?
一台压路机的前压轮长2米，直径是1.5米，一分钟可以转50周，问一分钟压路面积是多少？
<gadget id="calculator">3.14 * 1.5 * 2 * 50</gadget>
<output>471</output>

<result>471</result>