在下列结论中,正确的命题序号是( )(1)若两个向量相等,则它们的起点和终点分别

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问题:

在下列结论中,正确的命题序号是(  )
(1)若两个向量相等,则它们的起点和终点分别重合;
(2)模相等的两个平行向量是相等的向量;
(3)若
a
b
都是单位向量,则
a
=
b

(4)两个相等向量的模相等.
A.(2)(4)B.(3)(4)C.(4)D.(1)(3)
考点:真命题、假命题相等向量与共线向量的定义
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The question whether there is life on Mars (火星) has made the public think a lot for more than a century. The closest look showed Mars to be a dusty, cold world, covered by air too thin to breathe. A British spaceship and Europe's Mars spaceship plan to land on Mars or enter orbit (轨道) around it. One of the NASA’s (美国宇航局) spaceships is expected to land on January 3, the other is going to land on the opposite side of Mars on January 24. Since 1960, over twenty spaceships sent to Mars have failed. Most have been lost on flying up or landing because those are the most difficult times of any flights.     Scientists wanted to find out whether there was water in Mars. In October, a team of scientists reported that Mars had been a dry wasteland. But weeks later, a second team reported differently that they had found some marks showed clearly that they were made by the rivers. Such marks told us that Mars was a warmer place billions of years ago — just as life first appeared here on Earth. Scientists at once raise a question: if what they said is true, what happened on Mars? Then what about the earth?

小题1:Which is right about Mars?

A.It’s cold without dust.

B.There is no water or air.

C.It’s warm with some thin air.

D.It’s a dusty, cold world almost without air.小题2:Two NASA’s spaceships _______________.

A.will land on the different sides of Mars

B.will land on the same day

C.will enter orbit around Mars

D.will land with a man小题3:The most difficult times of a flight are _______________.

A.taking off

B.flying up and arriving

C.entering the orbit and landing

D.leaving the earth and entering the orbit小题4:A team of scientists reported that there might be_____________ in Mars.

A.nothing but air

B.nothing

C.water billions of years ago

D.thick air and lakes小题5:What are scientists worried about when they raise the question?

A.Life disappeared on Mars.

B.Spaceships can’t land on Mars.

C.The air on the earth gets less and less.

D.The earth might be changed like Mars

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最主要的治疗手段为

A.化学疗法

B.手术治疗

C.放射疗法

D.中药治疗

E.激素治疗

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补写出下列名篇名句中的空缺部分。(共8分,每空1分)

(1)_________________,朝不虑夕。

(2) _________________,在地愿为连理枝。 _________________,此恨绵绵无绝期。

(3)外无期功强近之亲,_________________。_________________,形影相吊。

(4)_________________,举杯断绝歌路难。

(5)_________________,长使英雄泪满襟

(6)_________________,千载谁堪伯仲间。

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混凝土立方体试块抗压强度低于标准值的概率应为()

A、5%

B、10%

C、15%

D、20%

题型:选择题

根据《中华人民共和国行政许可法》,下列法律原则中,不属于行政询:u-I法基本原则的是()。

A.法定原则

B.信赖保护原则

C.过错责任原则

D.公开、公平、公正原则

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