The hour hand on a clock face is 5 cm long, how many centimeters does the tip of the hour hand travel from 8 am to 2 pm?
一个钟面上的时针长5厘米，从上午8时到下午2时，时针尖端走了多少厘米？
<gadget id="calculator">5 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">2 * 3.14 * (5/2)</gadget>
<output>15.7</output>

<result>15.7</result>