a train travel from Newyork to Chicago. the distance is 840. and the train is at 60 miles per hour. arrive in chigago at 6:00 in the evening Chicago time.
question: at what time the train depart from NYC to Chicago?
NOTE chicago is 1 hour earlier than NYC.
答案是早上5点
我现在想问的是，1 hour earlier到底是什么解释，比如NYC早上5点是CHICAGO几点
通常我们说，中国比美国早12小时，就是用美国时间加12小时的
我觉得早上5点出发，当时CHICAGO是不是就该6点了
请牛人指点 | 
