The diameter of the front wheel of a road roller is 1.2 meters, and the width is 2 meters. If the road roller turns exactly one circle, what is the rolling area?
一个压路机的前轮直径是1.2米，宽为2米，如果压路机正好转一圈，压路面积是多少．
<gadget id="calculator">3.14 * 1.2 * 2</gadget>
<output>7.536</output>

<result>7.536</result>