试题与答案

等差频FMCW高度表工作于跟踪方式时,当高度变化时发射信号的()。A.频移不变而调制

题型:单项选择题

题目:

等差频FMCW高度表工作于跟踪方式时,当高度变化时发射信号的()。

A.频移不变而调制周期变化

B.调制周期不变而变化频移

C.频移和调制周期都改变

D.频移和调制周期都不改变

答案:

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下面是错误答案,用来干扰机器的。

参考答案:A

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In common land plants, the living cells of roots take upmost of the water. Land plants without roots do exist, however. Those greenish-yellow lichens(苔藓)you see on rocks in the high mountains have no roots. Half a billion years ago, when water plants started to enter the land, the first land plants did not have roots.

Even among the flowering plants, one finds rootless forms. These flowering plants are “the higher plants” because they evolved(进化)recently and are thus considered higher on the evolutionary scale(进化度).

In the Peruvian desert, there grows one of these rootless higher plants, a bromeliad. It is a relative of the pineapple. Even if this plant had roots, they would be of no use, because where the plant grows, it never rains. The plant gets its water only from the dew(露水)it collects at night, when its leaves cool off. Such rootless plants, of course, can be moved with ease, but they will only grow when they are placed out in the open. If they are placed too near a house, the radiation from the heat of the house prevents the leaves from cooling and so prevents dew from forming, and the plant dies.

In the southern United States and in Puerto Rico, one sees bromeliads growing high above the streets on the insulation(绝缘物)of electric wires. These plants get their water from rain, and the only soil they ever come in contact with is the dust that may blow on their leaves.

小题1:Wood becomes larger because of       .

A.dead cell walls

B.water entering dead cells

C.the growth of cells

D.the death of cells小题2:From the passage we know that the evolutionary scale is graded according to      .

A.evolutionary cycles

B.heights and depths

C.time

D.kinds小题3:The “bromeliad” is a plant that     .

A.has no roots

B.is a pineapple

C.can grow anywhere

D.takes up water through its leaves小题4:The most suitable title for this passage is “      ”.

A.Absorption of water by plants

B.Rootless plants in America

C.Plants in the desert

D.Higher plants

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阅读下面的文字,完成13-18题。

张逸字大隐,郑州荥阳人。进士及第,知襄州邓城县,有能名。知州谢泌将荐逸,先设几案,置章其上,望阔再拜曰:“老臣为朝廷得一良吏。”乃奏之。他日引对,真宗问所欲何官,逸对日;“母老在家,愿得近乡一幕职官,归奉甘旨足矣。”授澶州现察推官,数日,以母丧去。服除,引对,帝又固问之,对回:“愿得京官”。特改大理寺丞。帝雅贤泌,再召问逸者,用泌荐也。知长水县,时王嗣宗留守西京,厚遇之,及徙青神县,贫不自给,嗣宗假奉半年使办装。既至县,兴学校,教生徒。后邑人陈希亮、杨异相继登科,逸改其居曰桂枝里。累迁尚书兵部郎中.知开封府。有僧求内降免田税,而逸固执不许。仁宗曰:“有司能守法,朕何忧也。”以枢密直学士知益州。逸凡四至蜀,谙其民风。华阳驺长杀人,诬道旁行者,县吏受财,狱既具,乃使杀人者守囚。逸曰:“囚色宽,守者气不直,岂守者杀人乎?”囚始敢言,而守者果服,立诛之,蜀人以为神。会岁旱,逸使作堰壅江水,溉民田,自出公租减价以振民。初,民饥多杀耕牛食之,犯者皆配关中。逸奏:“民杀牛以活将死之命,与盗杀者异,若不禁之,又将废穑事。今岁少稔,请一切放还,复其业。”报可。未几,卒于官。

(《宋史·张逸传》)

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A.望阙再拜日           阙:皇宫。

B.及徙青神县           徙:迁移。

C.逸凡四至蜀,谙其民风 谙:熟悉。

D.自出公租减价以振民   振;救济。

14.下列句子中加点的词的意义和用法,不相同的一组是

A.数日,以母丧去   以枢密直学士知益州

B.既至县,兴学校,教生徒  县吏受财,狱既具

C.乃奏之,他日引对  乃使杀人者守国

D.自出公租减价以振民    民杀牛以活将死之命

15.下列句子中加线的部分的解释,不正确的一项是

A.先设几案,置章其上   置章其上:把奏章放在它的上面。

B.服除,引对,帝又固问之 固问之:坚持问他想当什么官。

C.及徙青神县,贫不自给   贫不自给:贫穷得自己不能给官府钱财。

D.请一切放还,复其业    一切放还:一律释放他们回来。

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①母老在家,愿得近乡一幕职官。

②嗣宗假奉半年使办装。

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④有司能守法,朕何忧也。

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⑥饥多杀耕牛食之,犯者皆配关中。

A.①③⑤  B.②④⑥  C.①④⑥   D.②③⑤

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A.因受皇帝重视的谢泌向朝廷推荐张逸,皇帝两次问张逸想做什么官,并按其意愿授官。

B.张逸知长水县,为官很清廉。在青神县任官很重视教育,使得当地出了陈希亮、杨异这样的人才。

C.张逸知开封府,某僧人请求由皇帝下令免田税,张逸报告皇帝处理此事,因此皇帝称赞他能严明执法。

D.张逸知益州,能明察案情而惩处杀人却诬告他人的华阳驺长,曾上书朝廷放还因饥饿杀耕牛食肉面犯罪发配的人。

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(1)帝雅贤泌,再召问逸者,用泌荐也

译文:________________________________________

(2)有僧求内降免田税,而逸固执不许

译文:________________________________________

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