From 12:00 to 18:00, how many degrees does the hour hand rotate.
从12：00～18：00，时针旋转了多少度．
<gadget id="calculator">18 - 12</gadget>
<output>6</output>

<gadget id="calculator">360 / 12</gadget>
<output>30</output>

<gadget id="calculator">6 * 30</gadget>
<output>180</output>

<result>180</result>