The hour hand of a big clock on the square is 4 decimeters long. What is the area swept by the hour hand in one day and night?
广场上一个大钟的时针长4分米，一昼夜这根时针扫过的面积是多少
<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">3.14 * 16 * 2</gadget>
<output>100.48</output>

<result>100.48</result>