有φ75.9mm油管每米质量是13.22kg/m,该油管的长度15m,其总质量是多少

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问题:

有φ75.9mm油管每米质量是13.22kg/m,该油管的长度15m,其总质量是多少?(取小数点后一位数)

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已知集合A={x|1≤x≤4},B={x|x>k,k∈R},若A⊆B,则k取值的集合是(  )
A.{k|k≤1}B.{k|k<4}C.{k|k≤4}D.{k|k<1}
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阅读理解。

     Astronauts aboard the space station celebrated a space first on Wednesday by drinking water that had

been recycled from their urine (尿), sweat and water got from air. They said "cheers" to NASA workers

on the ground.

     The urine recycling system is needed for astronaut stations on the moon and Mars. It also will save NASA

money because it won't have to ship up as much water to the station by space shuttle or cargo rocket.

Besides, it's important as the space station is about to expand from three people living on board to six.

     The recycling system had been brought up to the space station last November, but it couldn't be used until

samples (样品) were tested back on earth. So when it came time to actually drink up, NASA made a big deal

of it. The three-man crew stood holding their drinks and congratulated engineers in two NASA centers that

worked on the system.

     "This is something that had been the stuff of science fiction," American astronaut Michael Barratt said

before taking a small mouthful. The taste is worth trying.

     The new system takes the combined urine of the crew from the toilet and moves it to a big tank, where

the water is boiled off, and the vapor is collected. The rest of the urine is thrown away. Then the water vapor

is mixed with water from air, and then it goes through filters (过滤器). When six crew members are aboard,

it can make about six gallons from urine in about six hours.

     "Some people may find the idea of drinking recycled urine distasteful, but it is also done on earth, but with

a lot longer time between urine and the tap," said Marybeth Edeen, the space station's national lab manager.

     The technology NASA developed for this system has already been used for quick water purification after

the 2004 Asian tsunami.

1. According to the text, the recycling system is important because _____.

A. it makes traveling to the moon for the average person possible

B. with it NASA won't need to ship any water up to the space station

C. it protects the environment in space by reducing the amount of waste

D. it can help meet the need for more water after the crew is expanded

2. Which is the RIGHT time order of the following events?

    a. The samples of the recycled water were tested on earth.

    b. Astronauts celebrated the space's first making water from urine.

    c. The recycling system was brought up to the space station.

    d. The technology for the system was used to quickly purify water.

A. a, d, c, b

B. a, c, b, d

C. d, c, a, b

D. d, a, c, b

3. From Paragraph. 5 we can know _____.

A. the process of recycling urine

B. the effect of the recycling system

C. an opinion on recycling urine

D. the theory behind the recycling system

6. What is the best title for the text?

A. Drink up: Space Station Recycles Urine to water

B. New Technology Is Used in the Space Station

C. The Research of NASA Has Made Great Progress

D. Good News: Water Recycled from Urine Tastes Good

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物业管理企业在实施物业管理活动过程中首先要( )。

A.接管验收物业

B.签订物业服务合同

C.收集物业资料

D.为客户办理入住手续

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( )不属于地籍调查的主要作用。

A.完善了国有土地间的土地权属界限

B.建立地籍管理信息库

C.为土地管理科学的研究积累资料

D.奠定了地籍管理的基础

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平衡力的方向与泵所产生的轴向力()。

A、相同

B、相反

C、相垂直

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