某质点在F1、F2和F3三个共点力作用下处于平衡状态,各力的方向所在直线如图所示

题型:选择题

问题:

某质点在F1、F2和F3三个共点力作用下处于平衡状态,各力的方向所在直线如图所示,各力的矢量起点均在O点,终点未画出.若sin37°=0.6,sin53°=0.8,则各力的大小关系是(  )

A.Fl:F2:F3=3:4:5

B.Fl:F2:F3=4:3:5

C.Fl:F2:F3=5:3:4

D.Fl:F2:F3=5:4:3

考点:滑动摩擦力、动摩擦因数力的合成共点力的平衡
题型:选择题

牙组织不包括()

A.牙质

B.釉质

C.牙骨质

D.牙髓

E.牙周膜

题型:选择题

早产儿男性体重1 450g,人工喂养。出生后6天出现腹胀,伴有呕吐,呕吐物中含有胆汁,继而出现腹泻,有黏液血便。查体:体温38℃,腹膨隆,叩鼓音,腹部未触及包块,肠鸣音弱。为明确诊断需进行一系列检查。

正确的诊断应该是

A.先天肥厚性幽门狭窄

B.肠套叠

C.肠扭转

D.胎粪性腹膜炎

E.新生儿出血坏死性小肠炎

题型:选择题

These days, there’s a popular cartoon named happy sheep and gray wolf. It’s an excellent Chinese cartoon, which tells the stories of happy sheep and gray wolf. The poor gray wolf is always trying hard to catch the sheep, but the sheep could always run away from the danger. The sheep are so clever and lovely that the cartoon gets all the children’s love. At the same time, the cartoon is full of humor. The children could learn more knowledge and enjoyment from it.

The cartoon is shown repeatedly on many TV channels.The Zhejiang Channel broadcasts the cartoon on weekends and the vacations; the Sichuan Channel broadcasts the cartoon for an hour in the evening; the Shandong Channel broadcasts it in the morning, while CCTV-3 broadcasts it at noon every day.

On one hand, the cartoon gets the children’s love because the happy sheep is really clever. He always has a way to work out any problem and save his friends. What’s more , there’re many things about happy sheep and gray wolf, such as the books, the toys, the pencil-box, the clothings, and so on. Children are happy to buy them. On the other hand, many adults (大人) also like the cartoon, for the gray wolf is regarded as the perfect husband with skills and effort. He invents many things just to catch a sheep for his wife. Though he is often hit by his wife, he always makes her happy without complaining (抱怨).

We can learn more from the cartoon, including the skills, the stories, the details, the humor, and so on. We could see the humor of Chinese type during the cartoon. But I don’t like its being shown so often. It may make the children spend more time on watching TV and it is bad for their health and study.

小题1:The underlined word “cartoon” in the first paragraph is ________.

A.a kind of picture

B.a kind of sheep

C.a kind of film

D.a kind of book小题2:Which channel is not mentioned in the passage.

A.Zhejiang Channel

B.Shandong Channel

C.Sichuan Channel

D.CCTV-1小题3:Why do many adults also like the cartoon Happy Sheep and Gray Wolf?

A.Because they like men like gray wolf.

B.Because they are still young.

C.Because they want to make their children happy.

D.Because there are many things about the happy sheep and the gray wolf.小题4: The author doesn’t like its being shown repeatedly because ________

A.he thinks children will feel bored after seeing it again and again

B.he is afraid that children’s health and study will be affected

C.he doesn’t like the cartoon himself.

D.he thinks it is a waste of money

题型:选择题

正是因为有了充足的奶制品作为食物来源,生活在呼伦贝尔大草原的牧民才能摄入足够的钙质。很明显,这种足够的钙质,对呼伦贝尔大草原的牧民拥有健壮的体魄是必不可少的。
以下哪项情况如果存在,最能削弱上述断定

A.有的呼伦贝尔大草原的牧民从食物中能摄入足够的钙质,且有健壮的体魄。
B.有的呼伦贝尔大草原的牧民不具有健壮的体魄,但从食物中摄入的钙质并不少。
C.有的呼伦贝尔大草原的牧民不具有健壮的体魄,他们从食物中不能摄入足够的钙质。
D.有的呼伦贝尔大草原的牧民有健壮的体魄,但没有充足的奶制品作为食物来源。
E.有的呼伦贝尔大草原的牧民没有健壮的体魄,但有充足的奶制品作为食物来源。

题型:选择题

医院科研管理基本程序由那几个步骤构成?

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