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【题目】(5分)在半径R=5 000 km的某星球表面,宇航员做了如下实验,实验装置如图甲所示,竖直平面内的光滑轨道由轨道AB和圆弧轨道BC组成,将质量m=0.2 kg的小球从轨道AB上高H处的某点静止滑下,用力传感器测出小球经过C点时对轨道的压力F,改变H的大小,可测出相应F的大小,F随H的变化如图乙所示。求:

(1)圆轨道的半径。

(2)该星球的第一宇宙速度。

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【题目】 ——Do you think we can get there on time?

——__________ the car doesn’t break down.

A. So long as B. Even though

C. As soon as D. As if

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【题目】How much ______the new dress ______you?

A. did; pay B. was; spend

C. was; take D. did; cost

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【题目】 I didn’t say I like it. ________I was very much against it.

A. At the same time B. Rather than

C. On the whole D. On the contrary

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【题目】冥王星与其附近的另一星体卡戎可视为双星系统质量比约为7:1,同时绕它们连线上某点O做匀速圆周运动由此可知,冥王星绕O点运动的

A.轨道半径约为卡戎的

B.角速度大小约为卡戎的

C.线速度大小约为卡戎的7倍

D.向心力大小约为卡戎的7倍

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【题目】She's such a quarrelsome woman. I don't know how you can ______ her.

A. put up B. put up with

C. stand up with D. stand with

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【题目】 It was when I got back to my apartment ______ I first came across my new neighbors.

A. who B. where C. which D. that

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【题目】When___for his views about his teaching job,Philip said he found it very interesting and rewarding

A.asking

B.asked

C.having asked

D.to be asked

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【题目】With the changes in the world’s climate, dinosaurs died, but many smaller animals lived on. It was the of

the fittest.

A. survival B. distinction

C. existence D. appearance

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【题目】下图为局部地区经纬网图。图中A点位于南纬70°AB为晨昏线的一段;此刻,北京处于白昼;近期,C地日出时刻越来越早。读图回答下列各题。

1

A. 10B. 8C. 17D. 15

2

A. 该日,大约在12月中旬

B. 该日,C地从西北方向日落

C. 该季节,珠江正值枯水期

D. 该季节,澳大利亚白昼比中国长

3

A. 东北 B. 东南 C. 西南 D. 西北

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