The roller of a road roller is 1.5 meters long and 1 meter in diameter. If it rolls 100 times, how many square meters of road surface can be pressed?
一台压路机的滚筒长1.5米，直径是1米，如果它滚动100周，可压的路面是多少平方米．
<gadget id="calculator">3.14 * 1 * 1.5</gadget>
<output>4.71</output>

<gadget id="calculator">4.71 * 100</gadget>
<output>471</output>

<result>471</result>