A large clock has a minute hand 40 cm long. From 12:00 noon to 13:00 noon, how many square centimeters does the minute hand sweep?
一只大钟，它的分针长40厘米．当从中午12时到13时，这根分针扫过的面积是多少平方厘米？
<gadget id="calculator">40 ** 2</gadget>
<output>1_600</output>

<gadget id="calculator">3.14 * 1_600</gadget>
<output>5_024</output>

<result>5_024</result>