请回答下列问题：

今年是新中国第一部宪法颁布60周年。下列关于我国宪法的叙述正确的有（  ）
①宪法具有最高的法律效力                       ②宪法规定国家生活的各项具体问题
③宪法规定公民的基本权利和义务           ④宪法的制定和修改程序比普通法律严格 

   Look at the centre circles of Diagram (图)A and Diagram B. Which of the centre circles looks larger? In fact, they are exactly the same size.
Then look at the picture on the right. What do you see? A vase? Or two faces？Does the picture change quickly from one to the other again and again? Maybe or maybe not, but you can never see them at the same time.

   “What’s happening? Is something wrong with my eyes?” You may wonder at what you see. Don’t worry. Here is how it goes:
When we look at things, our eyes send messages to our brains and then our brains interpret（解读）the information. However, sometimes our brains interpret the received information in a wrong way. It seems that our eyes are playing a joke on us. This often happens and we call it “visual illusion(视觉错误)”.
   Movie makers often make use of visual illusions. They make the objects around actors much smaller or bigger than usual. This makes us believe that the actors are much larger or smaller than they usually are. The movies Jurassic Parkand Honey I shrunk the kids just make use of visual illusions.

复数z=1-i,则$\frac{1}{z}+z$对应的点所在的象限为（     ）

北京市的别称是