的全微分dz为()。 A.A B.B C.C D.D

题型:单项选择题

问题:

的全微分dz为()。

A.A

B.B

C.C

D.D

考点:一级注册结构工程师一级结构师基础知识一级注册结构工程师基础部分上午试卷
题型:单项选择题

任务型读写(共10小题;每小题1分,满分10分)

阅读下面短文,根据所读内容在表格中的空白处填入恰当的单词。

注意:每空格只填一个单词。

As more students begin to use computers for longer periods of time, more of them are suffering from eyestrain (视疲劳).Just a few hours in front of a computer screen can make a person’s eyes feel tired and painful.A number of eye doctors have studied this growing problem and have found ways to deal with it.Following their advice will help keep computer users more comfortable.Here is some of the advice.

The light in a room shouldn’t be brighter than the computer screen itself.In many classrooms, however, the lights are far brighter than they should be..Students can block some of this light by wearing baseball caps if they’re allowed at school.

A special computer screen should be used to cut down on bright light because it is especially tiring to the eyes.Another problem to avoid is the wrong kind of contrast.It is best to have dark letters on a light background.This causes less eyestrain than light letters on a dark background.

Students should be seated so that they are looking down at the computer screen rather than straight ahead, which is a far more tiring angle.The top of the monitor should be slightly lower than the top of the head.

The length of time students spend in front of a computer screen leads greatly to eyestrain.Students should take frequent breaks by looking away from the screen every fifteen or twenty minutes.During that time they should either close there eyes or focus on an object at a distance. Long – term computer use can dry out the eyes, so students should remember to blink frequently while in front of the screen.

Title: Computers and Eyestrain

Common Problems  Doctor’s小题1:      

Room

lighting     Much brighter in many classrooms          Get the light小题2:   bright.

小题3:       something to block the light.

The screen       Too bright light.

Wrong kind of contrast.

Light letters.   小题4:      the strong light.

Use the 小题5:       kind of contrast.

Have dark letters on a light background.

小题6:      The top of the screen

小题7:      than the top of the head. Sit were you won’t look小题8:    at the serene.

Time        Spending too much time

小题9:     a computer screen.   小题10:      your eyes for a moment.

Look at something at a distance.

Blink often while using a computer.

题型:单项选择题

根据药物的性质、用药目的和给药途径,将原料药加工制成适合于医疗或预防应用的形式是()

A.中药药剂学

B.剂型

C.饮片

D.中成药

E.处方药

题型:单项选择题

下列对价值工程的目标,表述正确的是()。

A.尽力改进产品的功能

B.以一定的寿命周期成本,尽力提高产品的功能

C.最大程度地使价值系数变得最大

D.以最低的寿命周期成本,使产品具备它所必须具备的功能

题型:单项选择题

Hb的α亚基与O2结合后产生变构效应,其结果是

A.促进其他亚基与CO2结合
B.抑制其他亚基与O2结合
C.促进其他亚基与O2结合
D.促进α亚基与O2结合,抑制β亚基与O2结合
E.抑制α亚基与O2结合,促进β亚基与O2结合

题型:单项选择题

2011年一季度我国建筑业产值为16096.4亿元,其中,建筑工程产值14220.0亿元,安装工程产值1405.2亿元,其他471.2亿元。华东六省一市相关数据见下表:

下列判断不正确的有:()(1)2011年一季度,江西省建筑业每项产值在华东六省一市中都是最低(2)2011年一季度,江苏省建筑业产值比上海市高出139.9%(3)2011年一季度,华东六省一市建筑工程产值占其建筑业产值的比重均超过80%

A.0个

B.1个

C.2个

D.3个

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