多项选择题：客运专线无砟轨道基床表层级配碎石压实标准Ev2为（），Evd为（）。A、≥50MPa

题型：单项选择题 A1/A2型题

麻醉前给患者注射哌替啶的目的是（）

A.抑制呼吸

B.松弛肌肉

C.提高痛阈

D.抑制呼吸道分泌物

E.预防迷走神经兴奋

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题型：问答题

有A、B、C三种元素．A元素的单质是一种淡黄色的粉末，它在B元素的单质中燃烧发出蓝紫色火焰，C元素的单质是自然界中最轻的气体，它在B元素的单质中燃烧发出淡蓝色的火焰，则：

（1）A元素单质的名称为______；

（2）B元素的原子得到两个电子后的粒子符号为______；

（3）C元素的单质的化学式为______；

（4）A、B、C三种元素可形成的一种化合物的化学式为C₂AB_x，若A的化合价为+4价，则x的数值为______，该化合物的化学式为______．

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题型：单项选择题

下列不属于透析患者常用药物的是（）

A.磷结合剂

B.维生素D

C.维生素A

D.人促红素（EPO）

E.缓泻药

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题型：阅读理解

阅读理解。

As you climb into the hill country, the roads get dustier and rougher, and fewer cars can be seen.

Phonxay is one of the poorest districts of Laos, and many of its villages are only accessible by footpath.

Our destination this hot morning is a concrete water tank that can be found just off the road. A UK

organization helped to build it six years ago, and in the nearby village of Thapho, where clean drinking

water is scarce, it has made a big difference. The tank feeds six taps which in turn give water to over 800

people---it has improved things for almost every family, from schoolchildren to grannies.

But lately, we were told, the clean water supply has come under pressure from new arrivals, people

who have come down from the hill areas, and there are concerns that there will not be enough clean water to go round.

There are also serious worries about resources in Laos. The Chinese are building a 400km railway link, which could transform the landlocked country. About 150,000 Chinese workers will be involved. What

will this do to local clean water supplies? How will the workers be fed?

The vast majority of Laotians live on farms. But with foreign investors wanting to buy up land, local

people will have to be moved to make room for them. Heavily dependent on both foreign aid and foreign

investment, Laos still falls well behind its neighbours, although its economy has grown at about 6% a year

in the last decade. Its biggest economic problem is the lack of locally trained skilled workforce.

But there are reasons to be hopeful for the future. Laos is beautiful, and foreign tourism continues to grow: fortunately so far the fast-food chains and coffee bars common elsewhere are nowhere to be seen.

Although all local media are government-run, the Internet is not controlled and the BBC and CNN are

available to those with satellite dishes.

The government has also achieved impressive results in rural development, with communities benefiting not just from cleaner water but the construction of new schools and regular visits from medical teams.

Poverty will not be history in Laos within the next decade, but with small steps forward and a bit of outside help, the country could find itself out of the UN's least-developed category by 2020.

1. The underlined word "scarce" in paragraph 1 most probably means_________.

A. valuable

B. rare

C. infrequent

D. missing

2. What is putting pressure on the local supply of clean water?

A. Dust from the road is making the water dirtier.

B. There are too many taps accessing the water.

C. The population of the area is growing fast.

D. The coming summer will dry up rivers and lakes.

3. What is the most serious limitation on Laos' economic growth?

A. The lack of local skilled workers.

B. A poor transportation system.

C. Too much foreign aid.

D. Too many foreign workers.

4. According to the passage, which of the following is NOT a reason for Laos to be hopeful?

A. There are no fast-food restaurants in the country.

B. Laos has a variety of tourist attractions.

C. Information on the Internet is freely accessible.

D. The government owns all local media.

5. What is the best title for the passage?

A. Laos: small steps forward

B. Laos: slow-developing nations

C. Laos: least-developed land

D. Laos: landlocked country

客运专线无砟轨道基床表层级配碎石压实标准Ev2为（），Evd为（）。A、≥50MPa

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