轻质弹簧吊着小球静止在如图所示的A位置,现用水平外力F将小球缓慢拉到B位置,此时

题型:不定项选择

问题:

轻质弹簧吊着小球静止在如图所示的A位置,现用水平外力F将小球缓慢拉到B位置,此时弹簧与竖直方向的夹角为θ,在这一过程中,对于整个系统,下列说法正确的是

[ ]

A.系统的弹性势能不变

B.系统的弹性势能增加

C.系统的机械能不变

D.系统的机械能增加

考点:弹性势能机械能
题型:不定项选择

甲图是某个国家二战后经济发展时期人口出生率、死亡率和自然增长率的变动示意图,乙图是人口年龄构成示意图,回答题:

小题1:在20世纪末到21世纪初,该国人口再生产类型属于典型的(  )

A.原始型

B.传统型

C.过渡型

D.现代型小题2:根据甲图所示的人口变化趋势判断,今后该国人口工作的主要任务是(  )

A.继续保持较低的人口生育水平

B.遏制人口老龄化加速的势头

C.鼓励农村大量剩余劳动力向城市迁移

D.减少劳务输出人员的数量小题3:在乙图中,①、②、③、④四点所示人口年龄构成情况能够与该国1995年人口出生率、死亡率和自然增长率情况相符的是(  )

A.①

B.②

C.③

D.④

题型:不定项选择

证券经纪业务是指证券公司通过开立证券营业部接受客户的委托,帮助客户进行风险管理和投资咨询,并根据市场风险控制代理客户做出交易委托。 ( )

题型:不定项选择

下列关于高温作业分级依据的说法,不正确的是()。

A.常年从事接触高温作业工种,应以最热季节测量值为分级依据

B.接触高温作业工种,应以全年测量值的平均值为分级依据

C.季节性或不定期接触高温作业的工种,应以季节内最热月测量值为分级依据

D.室外作业的工种,应以夏季最热月晴天有太阳辐射时的测量值为分级依据

题型:不定项选择

People use their mouths for many things. They eat, talk, shout and sing. They smile and they kiss. In the English language, there are many expressions using the word“mouth”.

For example, if you say bad things about a person, the person might protest and say“Do not bad mouth me. ”Sometimes, people say something to a friend or family member that they later regret because it hurts that person’s feelings. Or they tell the person something they were not supposed to tell. The speaker might say:“I really put my foot in my mouth this time. ”If this should happen, the speaker might feel down in the mouth. In other words, he might feel sad for saying the wrong thing.

Another situation is when someone falsely claims another person said something, the other person might protest,“I did not say that . Do not put words in my mouth. ”

Some people have lots of money because they were born into a very rich family. There is an expression for this, too. You might say such a person“Born with a silver spoon in his mouth. ”This rich person is the opposite of a person who lives from hand to mouth. This person is very poor and only has enough money for the most important things in life, like food.

Parents might sometimes withhold(拒给)sweet food from a child as a form of punishment for saying bad things. For example, if a child says things she should not say to her parents, she might be described as a mouthy child. The parents might even tell the child to stop mouthing off.

But enough of all this talk, I have been running my mouth long enough.

小题1:In what kind of situation will a person say“Do not bad mouth me. ”?

A.When he feels down.

B.When he feels regretful.

C.When he is spoken ill of.

D.When he feels proud.小题2:If a person feels sorry for what he has said, he might say “_____”

A.Do not bad mouth me.

B.I really put my foot in my mouth this time.

C.Do not put words in my mouth.

D.Stop mouthing off.小题3:If a person lives from hand to mouth, it implies _____ .

A.he is badly-off

B.he is hard-working

C.he is well-off

D.he has enough to eat小题4:By saying“I have been running my mouth long enough.”, the speaker means “_____”

A.I have run a long way.

B.I have been a mouthy person.

C.I have learned a lot.

D.I have talked too much.

题型:不定项选择

安装井口设备时,必须有一名()统一指挥。

A、作业队技术员

B、作业队队长

C、测井工

D、操作工程师

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