图18-1-4所示结构在D点作用一水平力P=2kN,不计自重,则支座B的反力RB为(

题型:单项选择题

问题:

图18-1-4所示结构在D点作用一水平力P=2kN,不计自重,则支座B的反力RB为()。

A.RB=3kN,方向铅直向上

B.RB=3kN,方向铅直向下

C.RB=2kN,方向铅直向上

D.RB=2kN,方向铅直向下

考点:注册土木工程师岩土工程基础知识注册岩土工程师基础考试上午试题
题型:单项选择题

在下面语段的横线处补写结论句,使语段的意思完整明确。(不超过10个字)

新中国成立后,在极左思想的指导下,出版了几本当时极为流行的《中国通史》。不管作者学问多么大,名气多么高,在教条主义流行的年代,写出来的书绝对不可能不受其影响,有的是违反作者本意的产品。过去写通史,最早只写出商代,这样我们的历史只有三千多年,较之埃及、巴比伦,基至印度,瞠乎后矣。然而,近年来,由于考古工作的飞速进步,夏代的存在已经完全可以肯定。我们相信,随着考古发掘工作进一步的发展,中国的历史必将更会向前推进。关于中国文化发源地的广袤问题,过去一般的意见是在黄河流域。现在考古发掘工作告诉我们,长江流域也是中国文化发源地之一。过去只看到黄河流域一个地方,是不够的。今天我们再写历史,决不能再走这一条老路。

因此,我主张___________________________。

题型:单项选择题
目前国家提倡“低碳生活”是为了节能环保.下列说法中符合“低碳生活”理念的是(  )

A.教材用旧了就不要再循环使用

B.为了卫生而使用一次性碗筷

C.上学时能骑单车就尽量不坐汽车

D.为了方便而使用一次性塑料袋

题型:单项选择题

Animals seem to have the sense to eat when they are hungry and they do not eat more than their bodies need.It has been demonstrated(证明)that rats will, when given a choice over a period of time, prefer water with vitamins to water without vitamins even though there is no difference in taste or smell between the two water bottles.When a fragrant(香的)flavor(作料)was added to the vitamin-enriched water, the rats did seem to prefer it and kept drinking it ,even after the vitamins were switched to the clear water.In time, however, they broke the habit and went back to where the necessary vitamins were.

In a classic experiment, babies of 6 to 12 months old were placed in a cafeteria(自助) feeding arrangement, with a wide selection of baby food before them.They were given whatever food they pointed to or appeared interested in.We are told that at first they showed some unusual eating patterns, but that over a period of time they managed to select well-balanced diet.

So, in selecting food, rats and babies do seem to know and act on what's best for them.Apparently, there is a kind of “body wisdom”,  which humans soon lose.Most of us do not eat as wisely as we could.Many of our food preferences are culturally determined and influenced by long-established habits.Some people eat fox, dog and blackbirds, while we eat cows and pigs.So what people eat and how much they eat seems to be greatly influenced by what is going on around them.

小题1:In the experiment on rats, a fragrant flavor was added to the rats’ drinking water to _____________ .

A.encourage rats to drink vitamins-enriched water

B.find out rats’ preference in flavor

C.test whether rats know which drink is good for them

D.demonstrate the vitamins are tasteless小题2:According to the passage ,adults eating habits differ from those of babies because_________.

A.adults know better than babies what kind of food are good for their health

B.adults usually cannot resist the temptation of various delicious foods

C.adults' eating habits are closely related to the social and cultural customs

D.adults have more choices of food than babies in eating patterns小题3:The author implied in the passage that most of us_________.

A.eat a balanced diet

B.choose the food that is of nutrition

C.have the habits influenced by the surroundings

D.like to eat the food with a fragrant flavor.小题4:As far as their eating habits are concerned, babies and rats are similar in that_________.

A.both have the wisdom to choose a balanced diet

B.both prefer flavored food and drink

C.both have the same eating patterns

D.both develop a taste for the same kinds of flavors

题型:单项选择题

下列除哪项外均为药材荆芥的性状鉴别特征()

A.茎方柱形

B.叶互生

C.穗状轮伞花序

D.小坚果

E.气芳香,味微涩而辛凉

题型:单项选择题

使用手杖前应检查手杖各部件是否完好安全。

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