Teacher Wang arrives at school at 7:30 am and leaves at 5:30 pm every day, with a 2-hour break at noon. How many hours does Mr. Wang work at school every day?
王老师每天上午7时30分到校，下午5时30分离校，午间休息2小时．王老师每天在校工作多少小时
<gadget id="calculator">10 - 2</gadget>
<output>8</output>

<result>8</result>