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23.  Yiwu is short of water now

   Yes I think its very important for us to _______.

A waste  water         B save and protect water

C make the water dirty       D throw the rubbish into the river

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17. .-Would you like to see Beijing Opera with tonight?

-Id like to ,but Im afriend I_______,I have to write to my pen friend

A. need       B.needn,t       C can       .D can,t 

18  Dont forget to wash your hands_______you have meals

A until      B.before      C when       .D while

19  Ive just borrowed a CD player, but I dond know_______.

   You can read the instructions

A how to use   B.where to buy it    C when to return it   .D where to put it

20  ______do you spend on your homework every day?

A.How often      B.How long      C How many     .D How much

21  Yaoming is one of the best players in NBA We are all__________him

 A.angry with    Bstrict with     C worried about    .Dproud of

22  The programme“Xiuhu Stories”________on Yiwu TV twice  a  week

A.is shown    Bshowed    C will show   .  D is showing

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请从A.B.C.D四个选项中选出可以填入空白处的最佳选项

16.- Do you know the story of Goldilocks and the Three Bears?

  - Yes Ido Its______interesting story

A. a       B. an       C the       .D 不填

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第三节:听独白,请从A.B.C三个选项中选择正确的选项,完成信息记录表。

11. A. Car        B. Bus         C. Bike

12. A .4:00         B.5:00         C. .6:00

13. A.opposite       B. behind       C. inside

14. A. truck        B. driver        C. wall

15. A. left foot      B.left arm       C. right arm

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第二节:听长对话,请从A.B.C三个选项中选择正确的选项。

听下面一段较长的对话,回答第6~7两小题。

6.Who is the letter from ?

A. John        B. Betty       C. Alice

7.Where does the girl come from ?

A. London      B. Beijing       C.New York

听下面一段较长的对话,回答第8~10三小题。

8.Which club does the man want to jonh ?

A.The English club    B. The Japanese club    C. The French club

9.Whats the mans job ?

A. A doctor      B.A taxi driver      C.A businessman

10.Why does the man want to go john the club ?

A. Because he wants to go abroad

B. Because he wants to pass an English exam

C Because he wants to make more foreign friends

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第一节:听小对话,请从A.B.C三个选项中选择符合对话内容的图片。

1.What are they doing now ?

2.Which animal does Kate like best ?

3.Where would Bruce like to go this weekend ?

4.What did Tom have for lunch yesterday ?

5.How does Tina feel ?

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22.解法一:(1)取BC的中点H,连EH,易得EH是EF在平面AC上的射影,

   ∵BD⊥EH,∴由三垂线定理,得 EF⊥BD;      

又∵EF在平面AB1上的射影是B1E,由△BB1E∽△ABG,得B1E⊥BG,∴由三垂线定理,得 EF⊥BG,

 ∵BG∩BD=B,∵EF⊥平面GBD.            

(2)取C1D1的中点M,连EM,易得EM∥AD1,所以∠EFM就是异面直线AD1与EF所成的角,      

∵MF∥BD,∴EF⊥MF .在Rt△EFM中,由EM=,(a为正方体的棱长),EF=,得

∠EFM=30º.即异面直线AD1与EF所成的角为30º.    

解法二:(向量法)(1) 以AD为x轴,DC为y轴,DD1z轴建立空间坐标系,不妨设正方体的棱长为2,

则D(0,0,0),A(2,0,0),B(2,2,0),E(2,1,0),F(1,2,2),G(2,,0,1)  ,D1(0,0,2   )                                            

  ∵(2,2,0)·(1,-1,-2)=0,(0,-2,1)·(1,-1,-2)=0

,又∵BG∩BD=B,∵EF⊥平面GBD.       

(2)=(-2,0,2),=(1,-1,-2)     . =

即异面直线AD1与EF所成的角为30º.                 

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21.解:(I)

正面向上次数m
3
2
1
0
概率P(m)




 正面向上次数n
2
1
0
概率P(n)



(II)甲获胜,则m>n,当m=3时,n=2,1,0,其概率为 

            当m=2时,n=1,0. 其概率为

            当m=1时,n=0  其概率为   

所以,甲获胜的概率为          

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20.解:(I)∵ △为以点M为直角顶点的

等腰直角三角形,

∴ 

∵ 正三棱柱, 

∴ 底面ABC

 ∴ 在底面内的射影为CMAMCM

∵ 底面ABC为边长为a的正三角形, 

∴ 点MBC边的中点.   

(II)由(1)知AMAMCM∴ AM⊥平面,

 过点CCH于H, ∵ CH在平面内, ∴ CHAM

,有CH⊥平面

即CH为点C到平面AMC1的距离

由(1)知,

 

∴                 ∴

∴ 点C到平面的距离为底面边长为.       

(III)过点CCII,连HI, ∵ CH⊥平面

 ∴ HICI在平面内的射影,

∴ HI,故∠CIH是二面角的平面角.

 

在直角三角形中,

∴ ∠CIH=45°, ∴ 二面角的大小为45°  

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19.解:(1)令红色球为x个,则依题意得,  所以得x=15或x=21,又红色球多于白色球,所以x=21.所以红色球为21个,白色球为15个.            

(2)设从袋中任取3个小球,至少有一个红色球的事件为A,均为白色球的事件为B,

则P(B)=1-P(A)= =    

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