信息系统经济效益评价的方法不包括 （55） 。A．投入产出分析法 B．成本效益分析法

机械性肠梗阻最常见的原因是

A．肠套叠

B．肠道肿瘤

C．粘连性肠梗阻

D．炎性狭窄

E．粪便梗阻

在社会实践活动期间，某校组织学生前往安徽凤阳县小岗村参观，村干部向同学们生动地介绍了小岗村改革开放的历程。回答1~2题。

1、1978年12月，小岗村18户农民签定了“分田到户”的“秘密协议”，从此拉开了我国农村改革的序幕。这场改革极大地调动了农民的积极性，改变了农村的经济形势和社会面貌。这说明[ ]

A、社会存在是社会发展的决定力量

B、社会意识是推动社会进步的动力

C、人民群众是社会历史的创造者

D、群众的首创精神解决了社会基本矛盾

2、“小岗村的历史是改革开放的历史，小岗村是中国农村改革的缩影”。从中同学们可以领悟到哲学道理是[ ]

A、事物发展的前途都是光明的

B、矛盾的普遍性高于特殊性

C、矛盾是事物发展的源泉和动力

D、量变达到一定程度必然引起质变

阅读理解。

     Happy birthday! Do birthday really make people happy? Of course they do.Birthday celebrate the

day when we were born.Besides, that extra candle on the cake suggest another year of growth and

maturity (成熟)-or so we hope.We all like to imagine that we are getting wiser and not just older. Most

of us enjoy seeing the wonder of growth in others, as well. For instance, seeing our children develop and

learn new things makes us feel proud. For Americans, like people in most cultures, growing up is a

wonderful process. But growing old? That is a different story.

     Growing old is not exactly for people in youth-oriented (以年轻人为中心) American culture. Most

Americans like to look young, act young and feel young.As the old saying goes, "You're young as you

feel." Older people joke about how many years young they are, rather than how many years old. People

in some countries value the aged as a source of experience and wisdom.But Americans seem to favor

those that are young, or at least "young at heart".

     Many older Americans find the "golden years" to be anything but golden.Economically, "senior

citizens" often struggle just to get by. Retirement at the age of 65 brings a sharp decrease in personal

income.Social security benefits usually cannot make up the difference. Older people may suffer from

poor nutrition, medical care, and housing. Some even experience age discrimination(歧视).American

sociologist Pat Moore once dressed up like an older person and wandered city streets.She was often

treated rudely-even cheated and robbed.However, dressed as a young person, she received much more

respect.

     Unfortunately, the elderly population in America is increasing fast.Why? People are living longer.

Fewer babies are being born. And middle-aged "baby boomers" are rapidly entering the group of the

elderly. America may soon be a place where wrinkles(皱纹)are "in".Marketing experts are ready noticing

this growing group of consumer.

1.We can infer from the second paragraph that       .

A. young people lack experience and wisdom

B. American older people often joke about their old age

C. American culture is very young

D. different countries have different opinions on the old age

3.What does the underlined sentence in the third paragraph mean?

A. The golden years can make the old earn lots of money and receive good medical care.

B. The old in America are leading a hard life without good nutrition, medical care or housing.

C. The old in America have to retire at the age of 65.

D. American social security benefits are not good.

3.What does the underlined word "in" in the last paragraph mean?

A. serious              

B. cool

C. disappearing slowly

D. growing fast

4. According to this passage, which of the following statement is CORRECT?

A. The young are much more respected than the old in America.

B. The old are much more respected than the young in America.

C. Growing old makes people feel proud in America.

D. The young are often discriminated in America.

键槽磨损时，允许键槽尺寸加大重新配键，但加宽量不得超过原尺寸的（）

A.10%

B.15%

C.20%

D.25%

采煤工作面前方的应力集中区一般从工作面前方（）m开始。

A、1-3

B、2-4

C、5-8

D、8-10