There is a clock hanging in the hall. Its hour hand is 12 centimeters long. How many centimeters does the tip of the hour hand move in a day and night?
大厅里挂着一只钟，它的时针长12厘米，这根时针的尖端一昼夜走了多少厘米？
<gadget id="calculator">3.14 * 12</gadget>
<output>37.68</output>

<gadget id="calculator">37.68 * 2</gadget>
<output>75.36</output>

<result>75.36</result>