The clock rotates clockwise around the center of the clock face from 12 o'clock to 4 o'clock, what is the angle of rotation
时钟绕钟面圆心从12时顺时针旋转到4时，旋转的角度是多少度
<gadget id="calculator">360 / 12</gadget>
<output>30</output>

<gadget id="calculator">4 * 30</gadget>
<output>120</output>

<result>120</result>