已知某星球的平均密度是地球的n倍,半径是地球的k倍,地球的第一宇宙速度为υ,则该

题型:选择题

问题:

已知某星球的平均密度是地球的n倍,半径是地球的k倍,地球的第一宇宙速度为υ,则该星球的第一宇宙速度为(  )

A.

n
k
υ

B.nk

k
υ

C.k

n
υ

D.

nkυ

考点:万有引力定律的其他应用
题型:选择题

阅读下面短文,然后根据括号内所给汉语意思写出单词的正确形式(每空一词)

A boy carefully led his blind father to a seat in a noodle restaurant .

He called loudly for two bowls of beef noodles. When the restaurant owner was about to prepare the food, the boy suddenly 小题1:  (挥手,挥动)to him and whispered, “Only one bowl with beef ,the other without ---just plain noodles.”

小题2: (事实上)the boy had a light purse and couldn’t  小题3:  (买得起)two bowls of beef noodles. He called just for his father to know.

When the noodles were  小题4:   (为..端上,服务,招待),the father wasn’t in a hurry ; he used his chopsticks to search in his bowls ,trying to find a slice of beef. As soon as he succeeded in finding one, he picked it up and put it into his 小题5:  (儿子) bowl, saying   小题6:  (和善地,和蔼地), “Eat some more. Have enough food so as to study well.”

The boy accepted in 小题7:  ( 沉默,寂静) and then stealthily put the beef back to his father’s bowl.

Moved by what they had done, the restaurant owner asked a waiter to bring them a small side dish from the kitchen. The boy took小题8:他) for sending to a wrong table, but the owner came up explaining with a 小题9:   (微笑), “Today is my restaurant’s anniversary(周年纪念日).The dish is free.”

After they left, the owner cleared the bowls from the table and found some coins   小题10: (在……下) one of them. The sum is just the price of the dish. 

题型:选择题

在页式存储管理中,进行地址映射所依据的关键是()。

A.缓冲区

B.目录

C.页表

D.分区表

题型:选择题

下列说法中,正确的是

A.植物的芽都能发育成枝条

B.通常情况下,干瘪的种子或正在休眠的种子不能萌发

C.植物生长所需要的无机盐只有含氮、含磷和含钾的无机盐

D.种子萌发需要的环境条件是:土壤、适宜的温度和一定的水分

题型:选择题

下列对村民委员会的说法正确的有

A.村民委员会成员由村民间接选举产生

B.国家机构的重要组成部分

C.由上一级政府任命

D.是村民自我管理、自我教育、自我服务的基层群众性自治组织

题型:选择题

曹备见自己的女友遭两个流氓调戏,前去制止,反遭攻击。此时,便衣警察张某赶到,未及表明自己的身份即迅速抓住曹备以制止殴斗。曹备视张某为流氓的同伙,随即拔刀将张某刺成重伤。曹备的行为属于______。

A.故意伤害

B.过失伤害

C.正当防卫

D.假想的防卫,应按意外事件处理

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