冬冬同学身高1.6m，她站在平面镜前3m处，她的像到镜面的距离为______m；

有一个等腰直角三角形，它的一个底角的度数是______．

从A、B、C、D四个选项中，选出与所给句子画线部分意义相同或相近并能替代的那一项。

1. She got mad at me and said she didn't want to be my best friend any more.[ ]

A. was angry with    

B.was angry at    

C. was disappointed with

D.was disappointed at

2. Lucy made a decision to tell her father about that.[ ]

A. wrote a letter  

B. sent an e-mail    

C. decided    

D. decided on

3. At first，the girl felt a bit nervous. [ ]

A. worried  

B. unhappy      

C. confident    

D. pleased

4. 一 I’m afraid I can't follow you,sir. Can you speak more slowly?

-Of course. [ ]

A. find    

B. run after      

C. understand    

D. keep

5. -Is this Mr Chen’s car？        

-I don't think so. He can't afford to pay for this kind of car.    A. is too poor to[ ]

A. is too poor to    

B. is able to    

C. is rich enough to    

D. doesn't want to

已知y是x的反比例函数，且当x=3时，y=8，那么当x=4时，y=______．

某土方工程，某月计划开挖160000m³，合同单价85元/m³，到月底实际完成土方量为180000m³，实际单价72元/m³，则该工程的以工作量表示的进度偏差（SV）为（）万元。

A.214

B.-214

C.170

D.-170

试述医疗市场的概念。