下列做法能体现同学间真正友谊的是（    ）

①同学被打时，“拔刀相助”                ②同学病了，主动帮他补习功课

③发生矛盾后，能换位思考                  ④对同学的错误给予诚恳的批评

Red Star Restaurant
The biggest and busiest restaurant in Jinan is seeking 20 waiters who have relevant (相关的) experiences in high-grade restaurants. About ¥800—1,500 per month.
Red Star Restaurant is located at 66 on Park Street.
Our phone number is 0531-8278-4560.
3 People wanted
Need 3 people who would like to work 4 evenings per week showing films. Earn $300 per week possibly. Call 469-867-6042.
Baby-sitter wanted
For a year. 3 days a week. Some flexible (灵活的) hours required.
Knowledge: above senior middle school.
Call 0431-478-9971.

sin（﹣600°）的值是（　　）

阅读文段，回答问题。

如梦令

李清照

昨夜雨疏风骤，

浓睡不消残酒。

试问卷帘人，

却道“海棠依旧”。

“知否，知否？

应是绿肥红瘦”。

小明在浴室中洗澡时，看到浴室内有两根金属水管，一根水管上有很多水滴，而另外一根水管上却没有水滴，他猜一根是热水管，一根是冷水管，但他又怕烫着不敢摸，请你帮他判断出有水滴的那根是冷水管还是热水管？说出你判断的理由．