不是脂质体的特点的是（） A.能选择性地分布于某些组织和器官 B.表面性质可改变 C

摄像机操作中，AWB是什么功能？（）

A.自动白平衡

B.自动曝光度

C.自动增益

D.自动快门速度

设f(x)＝x³＋ax²＋bx＋1的导数f′(x)满足f′(1)＝

2a，f′(2)＝－b，其中a，b∈R.

①求曲线y＝f(x)在点(1，f(1))处的切线方程；②设g(x)＝f′(x)e^－x，求g(x)的极值．

Five years ago, David Smith wore an expensive suit to work every day． "I was a clothes addict, "he jokes．" I used to carry a fresh suit to work with me so I could change if my clothes got wrinkled．" Today David wears casual clothes – khaki pants and sports shirt – to the office． He hardly ever wears a necktie． "I'm working harder than ever," David says, "and I need to feel comfortable．"

More and more companies are allowing their office workers to wear casual clothes to work． In the United States, the change from formal to casual office wear has been gradual． In the early 1990s, many companies allowed their employees to wear casual clothes on Friday, but only on Friday． This became known as "dress-down Friday" or "casual Friday．" "What started out as an extra one-day-a-week benefit for employees has really become an everyday thing．" said business consultant Maisly Jones．

Why have so many companies started allowing their employees to wear casual clothes? One reason is that it's easier for a company to attract new employees if it has a casual dress code． "A lot of young people don't want to dress up for work," says the owner of a software company, "so it's hard to hire people if you have a conservative dress code．" Another reason is that people seem happier and more productive when they are wearing comfortable clothes． In a study conducted by Levi Strauss and Company, 85 percent of employers said that they believe that casual dress improves employee morale （士气）． Only 4 percent of employers said that casual dress has a negative effect on productivity． Supporters of casual office wear also argue that a casual dress code helps them save money． "Suits are expensive, if you have to wear one every day," one person said． "For the same amount of money, you can buy a lot more casual clothes．"

小题1:David Smith refers to himself as having been "a clothes addict," because        ．  

A．he often wore khaki pants and a sports shirt

B．he couldn't stand a clean appearance

C．he wanted his clothes to look neat all the time

D．he didn't want to spend much money on clothes小题2:David Smith wears casual clothes now, because        ．  

A．they make him feel at ease when working

B．he cannot afford to buy expensive clothes

C．he looks handsome in casual clothes

D．he no longer works for any company小题3:According to this passage, which of the following statements is FALSE? 

A．Many employees don't like a conservative dress code．

B．Comfortable clothes make employees more productive．

C．A casual clothes code is welcomed by young employees．

D．All the employers in the U．S． are for casual office wear．小题4:According to this passage, which of the following statements is TRUE?   

A．Company workers started to dress down about twenty years ago．

B．Dress-down has become an everyday phenomenon since the early 1990s．

C．"Dress-down Friday" was first given as a favor from employers．

D．Many workers want to wear casual clothes to impress people．小题5:In this passage, the following advantages of casual office wear are mentioned except         ．    

A．saving employees' money

B．making employees more attractive

C．improving employees' motivation

D．making employees happier

青少年正处于生长发育的关键时期，不应该吸烟、喝酒。           （    ）

生产企业出口的视同自产货物，可以实行“免、抵、退”税管理办法。下列货物视同自产货物的有( )。

A．外购的与本企业所生产的产品名称、性能相同，使用本企业注册商标，并出口给进口本企业自产货物的外商的产品

B．外购的与本企业所生产的产品配套出口，不经过本企业加工或组装，出口后能直接与本企业自产货物组合成成套产品，并出口给进口本企业自产货物的外商的产品

C．外购的与本企业所生产的产品配套出口，出口给进口本企业自产货物外商的，用于维修本企业出口的自产货物的零部件

D．用本企业生产的货物再委托深加工收回的货物，出口给进口本企业代理出口货物的外商

E．委托加工收回的与本企业所生产的产品名称、性能不同的产品，出口给进口本企业自产货物的外商的产品