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Schedule a Tour

    University of South Carolina （USC) is famous for its warm southern hospitality（好客）. Schedule a visit and feel it in person. Our walking tours are led by current students, called University Ambassadors, who are looking forward to telling you what it's like to live and study in USC. Our walking tours run Monday through Friday and most are around 2 hours. The university will be closed on Tuesday, July 4, 2017 in observance of the holiday. We welcome your visit year round and will be ready for you, rain or shine. Please refer to the list below to determine which tour is best for you and remember to book at least two weeks in advance.

①函数 $y=\tan \left(x+\frac{\pi }{4}\right)$ 的定义域是 $\left\{x|x\ne \frac{\pi }{4}+k\pi ,k\in Z\right\}$ ；

②已知 $\sin a=\frac{1}{2}$ ，且α∈0，2π，则α的取值集合是 $\left\{\frac{\pi }{6}\right\}$ ；

③函数f（x）=sin2x+acos2x的图象关于直线 $x=-\frac{\pi }{8}$ 对称，则a的值等于﹣1；

④函数y=cos²x+sinx的最小值为﹣1．

把你认为正确的命题的序号都填在横线上____．

下列有关人体水分调节的叙述中，正确的是（　　）