The length of the minute hand of a clock is 12 cm. If it travels for 1 hour, what is the total length of the route traveled by the tip of the minute hand?
一个时钟的分针长12厘米，它走1小时，分针的针尖所经过的路线的总长为多少．
<gadget id="calculator">2 * 3.14 * 12</gadget>
<output>75.36</output>

<result>75.36</result>