The length of a road roller is 1.5m, and the diameter of the roller is 1.5m. If it rolls 20 times, how many square meters can be rolled?
一种压路机的滚筒长1.5m，滚筒的直径是1.5m，如果它滚动20圈，一共可以压路多少平方米？
<gadget id="calculator">3.14 * 1.5 * 20 * 1.5</gadget>
<output>141.3</output>

<result>141.3</result>