The hour hand of a big clock in a customs building is 1.8 meters long. From 11 am to 4 pm, how many square meters does the hour hand sweep?
某海关大楼的大钟时针长1.8米，从上午11点到下午4点，时针扫过的面积是多少平方米？
<gadget id="calculator">1.8 ** 2</gadget>
<output>3.24</output>

<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">3.14 * 3.24 * (5/12)</gadget>
<output>4.239</output>

<result>4.239</result>