The roller of a road roller is a cylinder with a diameter of 1 meter at the bottom and a length of 1.5 meters. If it rotates 4 times, how many square meters will be rolled.
一辆压路机的滚筒是一个圆柱，它的底面直径是l米，长是1.5米，如果它转4圈，一共压路多少平方米．
<gadget id="calculator">3.14 * 1 * 1.5 * 4</gadget>
<output>18.84</output>

<result>18.84</result>