某行星和地球绕太阳公转的轨道均可视为圆。每过N年,该行星会运动到日地连线的延长线

题型:选择题

问题:

某行星和地球绕太阳公转的轨道均可视为圆。每过N年,该行星会运动到日地连线的延长线上,如图所示,该行星与地球的公转半径之比为

[ ]

A.

B.

C.

D.

考点:万有引力定律的其他应用
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Dear friend,

I am an American (美国的 ) girl. My name is Alice Green. I am a middle school student. I am fifteen. I have two brothers. They are middle school students, too. We go to school from Monday to Friday. We don't have any classes on Saturdays and Sundays. My father and mother are teachers. They always say China is great. I like reading. I am reading a Chinese book. I think it's very interesting. My brothers and I like playing football and basketball. What sports do you like?

Let's be good pen pals (笔友), OK? Please write to me soon.

Yours,

Alice Green

小题1:How old is Alice Green?

A.13.

B.14.

C.15.

D.16.小题2:When do they go to school?

A.They go to school from Saturday to Friday.

B.They go to school from Monday to Saturday.

C.They go to school on weekends.

D.They go to school from Monday to Friday.小题3: What do Alice and her brother like?

A.Reading books.

B.Playing soccer and basketball.

C.Writing to pen pals.

D.Playing computer games.小题4:Why does Alice Green write this letter?

A.Because she wants to come to China.

B.Because she wants to make a pen pal in China.

C.Because she likes reading Chinese books.

D.Because her mother asks her to do.

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水在生物体的许多化学反应中充当[ ]

A.溶剂

B.催化剂

C.载体

D.还原剂

题型:选择题

下列各句中,标点符号使用正确的一句是 (  )

A.最近两天,京津地区、华北中南部、黄淮、江淮、汉水流域、贵州等地的日平均气温达到了入夏以来的最高值。

B.《新民丛报》虽然名为“报”,其实却是期刊,是梁启超等人于1902年在日本横滨创办的,曾产生过较大影响。

C.在市场竞争日益激烈的当下,他不得不认真思考公司的业绩为什么会下滑,怎样才能打开产品的销路?

D.新鲜大米,手感滑爽,米粒光洁,透明度好,腹白很小(米粒上呈乳白色的部分),做出的米饭清香可口。

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发射机输出功率为50W,综合测试仪最大允许注入功率亦为50W,在()时RF通路上必须串接合适的衰减器。

A.测试载波输出功率

B.测试载波工作频率

C.测试调制度大小

题型:选择题

各项建设用地对地形的坡度最敏感的项目是( )。

A.居住用地
B.城市道路
C.机场用地
D.铁路站场

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