题目内容：

A group of students from the US have been in China for a week. Here is part of their chat history (聊天记录) on WeChat.

20:45

      Hi, everybody! Anything to share today?

20:49

      Yes. I went to a restaurant to have dinner with some friends this evening.

When we finished the meal, the waiter brought us the bill. It was 270 yuan.

We gave him 300 yuan and left 30 as a tip(小费) for his service(职务).

To our surprise, he returned us the change!

      Really? How kind he is!

20:53

      @Sunny It’s different form that of the US. I worked in a restaurant in my free time. I accepted tips. Well, something interesting happened to me this morning…

20:55

      I couldn’t find the bus stop. I came up to a man who was walking near me and showed him the bus number. He nodded and asked me to follow. We walked for about 10 minutes and finally got to the bus stop. I wanted to give him a hug (拥抱) to show thanks, but he just said goodbye and walked away. I couldn’t believe that he had taken so much trouble for a stranger(陌生人)!

      It seems that Chinese people don’t usually hug.

      I guess so. It’s really unforgettable!

21:02

      I agree. The Chinese people I have met these days are all so friendly, polite

And helpful. Well will enjoy the rest of our trip for sure.

1.How much was Sunny’s bill?

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2.Did Stone find the bus stop in the end?

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3.What are the group of students mainly talking about?

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4.Do you think it is necessary for Sunny to give tips for the service? Why or why not?

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