Xiaoming walks an average of 68 meters per minute, and it takes him 20 minutes to walk from home to school. If he goes back and forth twice a day and goes to school 5 days a week, how much time does Xiaoming spend on his way to and from school every week?
小名平均每分钟走68米，他从家到学校要走20分钟，如果他每天往返两次，每周上学5天，小名每星期在上学和放学路上要花多少时间？
<gadget id="calculator">20 * 4 * 5</gadget>
<output>400</output>

<result>400</result>