赣州市公汽公司为了保证人们从公汽后门上下车时的安全,在无人售票车上安装了“车载电

题型:填空题

问题:

赣州市公汽公司为了保证人们从公汽后门上下车时的安全,在无人售票车上安装了“车载电视监控器”。如图所示是该装置的光学系统,图中的摄像头的工作原理相当________透镜,成________像。

考点:生活中的其他透镜(照相机,放大镜,投影仪等)
题型:填空题

在等腰三角形ABC中,AB=AC,一边上的中线BD将这个三角形的周长分为15和12两部分,则这个等腰三角形的底边长为[ ]

A.7

B.7或11

C.11

D.7或10

题型:填空题

阅读理解。

     Sue is 13 years old today. She has a birthday party. Her friends Amy, Lily and Kate come to her home.   

     Sue: Sit down and have a cup of tea.   

     Her friends: Thank you. Happy birthday, Sue.   

     Amy: Here is a cake for you. I'm sorry it's too small. The shop doesn't sell the big ones and Lily likes it

             very much.   

     Lily: I made a card for you. Happy birthday to you, Sue.   

     Kate: Sue, this hat is my present for you, do you like it?   

     Sue: Thank you very much. I like all of your presents for me. Let's sing and eat the cake.   

     (They jump with joy and begin the birthday party.)

1. Whose birthday is it?

A. Kate.

B. Sue.

C. Amy.

2. Who made a card for Sue?

A. Lily.

B. Kate.

C. Amy.

3. Who gives a hat to Sue?

A. Lily.

B. Kate.

C. Amy.

4. Who gives a cake to Sue?

A. Kate.

B. Lily.

C. Amy.

5. What does Sue like?

A. The card.

B. The hat and the cake.

C. A and B.

题型:填空题

.(每空1分共6分)随着网络时代的发展,淮北市大力推广光纤宽带上网。如图是光缆的结构示意图,其中的光纤由高纯度的二氧化硅制成。

(1)光缆中属于有机合成材料的      ,钢和生铁在组成上的最大差别是            

(2)废光缆中的一种金属可用于制取氢气,不选择另一种金属的理由是               。写出该金属制氢气的化学方程式                        

(3)请你推测钢丝在光缆中所起的作用           

题型:填空题

增感屏的应用注意事项中,错误的是

A.不可放于潮湿处
B.宜防于高温干燥处
C.暗盒直立放置,并关闭好暗盒
D.驱尘时可用软毛刷
E.避免强光照射

题型:填空题

不属于遗传代谢性疾病的是()

A.18-三体综合征

B.21-三体综合征

C.苯丙酮尿症

D.散发性呆小病

E.糖原累积病

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