对于有过热器的锅炉，应保证（）上的安全阀先开启。A、省煤器B、锅筒C、过热器

Because of the development of agriculture, the area of land affected by sand has gradually increased. During the 1950s and 1960s the land affected by sand expanded on average into 1,600 square kilometers per year. By the 1990s, the area had reached 2,500 square kilometers per year.  This kind of situation is particularly serious in many regions upwind(逆风的) from Beijing. Fengning City in Hebei Province and Duolun City in Inner Mongolia lie to the north of Beijing, and in the last 50 years the population of these two cities has grown by 2 to 3 times. In order to obtain more resources, the inhabitants have been busy with  heavy farming, tree-cutting and keeping animals. The result is that the soil which has sustained damage, and the sand layer below the earth is now exposed on the ground and the ground is rapidly being controlled by the spread of sand.

China has already noticed this problem, and has take measures to save the land. Nowadays, some land used for farming has returned to forestland and grassland. The Chinese government announced that it would invest more than RMB 600,000,000 to control Beijing’s sandstorms in the coming years. Only by decreasing the damage caused by man and restoring the natural environment will it be possible to well control the sources of the sand and dust. We hope in the not-distant future, we will solve the problem successfully and effectively.  

63. Compared with 50s and 60s, the land affected by sand increased by _____ square kilometers by the 1990s.

A. 1,600        B. 2,500         C. 900          D. 1,100         

64. Which of the following is NOT the cause of the damaged land?                      

A.People use the resources too much.

B.People keep animals which need more grain.

C.People prepare too much land to grow crops.

D.People cut a lot of forests and raise animals.

65. The major measure that Chinese government has taken is _____.                                                          

A.controlling the growth of the population     

B. making better use of natural resources

C. killing fewer animals and cutting fewer trees   

D. returning some land to forestland and grassland

66.According to the passage, it can be inferred that _____ was the major factor of the environmental damage.

A. man       B. animal      C. nature    D. desert 

患者，男，28岁，车祸致头面部损伤半小时。查体：意识模糊，烦躁不安，面度轻度发绀，吸气时锁骨上窝、剑突下、肋间隙内陷；面部检查见上颌骨无活动，下牙弓变窄，下前牙骨段活动、后移，口腔内无明显异物。患者可能发生（）

A.吸入性窒息

B.脱位性窒息

C.狭窄性窒息

D.阀门性窒息

E.阻塞性窒息

我国综合类证券经营机构注册资本最低限额为 ( )

A．3000万

B．500万

C．1亿元

D．5亿元

MRI检查技术中，“在病变尚未出现形态变化之前，利用局部功能变化来形成图像，达到早期诊断的目的”属于（）

A.脂肪抑制

B.水成像MRI

C.自旋回波序列

D.功能MRI（fMRI）

E.磁共振血管成像（MRA）

OUML是一种面向对象的统一建模语言。它包含十种图，其中，用例图展示了外部ACTOR与系统所提供的用例之间的连接，UML中的外部ACTOR是指 (33) 。状态图指明了对象所有可能的状态以及状态间的迁移。如果一个并发的状态由N个并发的子状态图组成，那么，该并发状态在某时刻的状态由 (34) 个子状态图中各取一个状态组合而成。协作图描述了协作的 (35) 之间的交互和链接。

A．每一

B．任意一

C．任意二

D．任意M(

)