What is the angle of the hour hand on the clock face after 3 hours.
钟面上的时针，走3小时后，走过的角度是多少度．
<gadget id="calculator">360 / 12</gadget>
<output>30</output>

<gadget id="calculator">30 * 3</gadget>
<output>90</output>

<result>90</result>