根据《水利水电工程施工组织设计规范》(SL 303-2004),施工组织设计中,当坝

题型:单项选择题

问题:

根据《水利水电工程施工组织设计规范》(SL 303-2004),施工组织设计中,当坝顶填筑高程超过围堰堰顶高程时,坝前拦洪库容为0.8亿m3的混凝土结构坝体施工期临时度汛洪水标准为( )年。

A.≥100
B.100~50
C.50~20
D.20~10

考点:二级建造师水利水电工程水利水电工程管理与实务
题型:单项选择题

钎焊时()。

A.被焊金属熔化

B.钎料熔化

C.被焊金属和钎料都熔化

D.被焊金属和钎料都不熔化

题型:单项选择题

     An American space company says a powerful new rocket should be ready for a test launch by the

end of 2012. The company is Space Exploration Technologies, or SpaceX. Its new rocket is called the

Falcon Heavy.

     Company officials say it'll be able to transport satellites or spacecraft weighing up to 53 metric tons

into orbit. Fiftythree metric tons is 117,000 pounds. That load weight is double the capacity of NASA

space shuttles. The space agency is retiring its shuttles after thirty years.

     Elon Musk is the chief executive officer of SpaceX. He says the Falcon Heavy will be the second

most powerful rocket ever. He says it was designed to carry satellites and other equipment into space.

He says the rocket was designed to meet NASA's ratings for human flight safety. So it could someday

be used to carry astronauts and other travelers into space.

     Mr. Musk says the Falcon Heavy could also be used for missions(任务) like carrying a robotic lander

to collect samples from Mars. He says, "It has so much more capability than any other vehicle that I think we can start to consider missions like a Mars sample return, which requires a tremendous amount of lift

capability because you've got to send a lander to Mars that still has enough propellant(推进物) to return

to Earth."

     The first launch is planned from the company’s launch site at Vandenberg Air Force Base in California. A launch from Cape Canaveral, Florida, is expected in late 2013 or 2014.

     In time, SpaceX hopes to launch ten Falcon Heavy rockets a year. It says the rocket should cut back

on launch costs to about 2,000 dollars a kilogram.

     SpaceX already has a billionandahalfdollar deal with NASA to use a smaller rocket to transport

cargo(货物) to the International Space Station. The rocket is the Falcon 9, and the deal is for after the

two last shuttles-Endeavour and Atlantis-are retired this year.

1. What do we know about the feature of the new rocket from the second paragraph?

(No more than 11 words)

________________________________________________________________________

2. Why did SpaceX want to design the new rocket?(No more than 16 words)

________________________________________________________________________

3. Why can the new rocket be used to carry a robotic lander to collect samples from Mars?

(No more 6 words)

________________________________________________________________________

4. What will SpaceX do for the NASA after Endeavour and Atlantis are retired?

(No more than 14 words)

________________________________________________________________________

题型:单项选择题

与细菌L型比较,支原体()

A.形态高度不规则

B.任何情况下都不能变成细菌

C.能通过滤菌器

D.无细胞壁

E.菌落呈荷包蛋样

题型:单项选择题

下列关于医患双方权利的提法中,错误的是()

A.维护患者的权利是医务人员、医疗卫生机构和社会的天职

B.维护医务人员的权利也是患者、医疗卫生机构和社会的义务

C.在处理维护医患双方权利的关系时,要把维护患者的权利放在优先的地位

D.维护患者权利的关键是保证不发生医患纠纷

E.维护医务人员权利的关键是尊重其人格尊严和人身安全

题型:单项选择题

石阡有哪些村寨列入贵州省500个特色民族村寨?

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