对于任意非零实数a，b，定义运算“☆”如下：a☆b=a-b2ab，则2☆1+3☆

阅读理解。

     These days the subject of security (安全) on campus is talked about quite often. Some students' mobile

phones are stolen, some students fight with and hurt one another, and others are knocked down by the fast

running bikes or cars.

     These problems arc common on campus. I think there are three causes for these. Firstly, some students

do not take good care of their properties. They are still young and not careful enough. Secondly, some

students want to do everything well. They want to be the winners in exams, and they also want to be the

winners in fightings. And thirdly, the campus guards (保安) do not carry on their duties well. They don' t

regulate the traffic in the busy hour.

     In order to have a secure campus, all the students should be very careful about their properties. They

should also mind their behaviors (举止) and act politely. The campus guards are supposed to be devoted

(致力于) to the security on campus, and it is their duty to safeguard (维护) a secure campus to help provide

a good environment for the students.

1. According to the passage, some students' _______ are stolen.

A. books

B. clocks

C. knives

D. mobile phones

2. The passage tells us there are _______ causes for the problems.

A. 2

B. 3

C. 4

D. 5

3. Some students want to be the _______ in exams and fightings.

A. players

B. singers

C. winners

D. teachers

4. The underlined word in Paragraph 2 "regulate" means "_______".

A. 关心

B. 维持

C. 赞同

D. 调节

5. This passage is mainly about _______.

A. how to make the campus safe

B. how to protect the students

C. security rules on campus

D. the importance of security campus

在数据库管理系统中，下面哪一项不是数据库存取的功能模块

A．事务管理程序模块

B．数据更新程序模块

C．交互式程序查询模块

D．查询处理程序模块

流行病学研究对象的三个层次是（）。

A.传染病、非传染病、慢性病

B.疾病、伤害、健康

C.地方病、非传染病、寄生虫病

D.残疾、弱智、生理缺陷

E.伤害、缺陷、意外

如果二氧化碳气体超量产生，就会在大气层中聚集，使全球气候出现令人讨厌的温 室效应。在绿色植被覆盖的地方，特别是在森林中，通过光合作用，绿色植物吸收空气中的二氧化碳，放出氧气。因此，从这个意义上，绿色植被特别是森林的破坏，就意味着在“生产”二氧化碳。工厂中对由植物生成的燃料的耗用产生了大量的二氧化碳气体，这些燃料包 括木材、煤和石油。上述断定最能支持以下哪项结论

A．如果地球上的绿色植被特别是森林受到严重破坏，将使全球气候不可避免地出现温室效应。

B．只要有效地保护好地球上的绿色植被特别是森林，那么，即使工厂超量耗用由植物生成的燃料，也不会使全球的气候出现温室效应。

C．如果各国工厂耗用的由植物生成的燃料超过了一定的限度，那将不可避免地使全球气候出现温室效应，除非全球的绿色植被特别是森林得到足够良好的保护。

D．只要各国工厂耗用的由植物生成的燃料控制在一定的限度内，就可使全球气候的温室效应避免出现。

按原稿的颜色特征，原稿可以分为（）。

A、彩色原稿彩

B、黑白原稿

C、网目调原稿

D、线划稿

E、连续调原稿