The minute hand of an alarm clock is 10 cm long. From 12:00 noon to 12:30 noon, how many centimeters does the tip of the minute hand travel?
一个闹钟的分针长10cm，从中午12：00到12：30，分针的尖端走过多少cm的路程．
<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 10 * 1</gadget>
<output>31.4</output>

<result>31.4</result>