航空运单具有承运合同、货物收据、报关凭证、保险证明等作用。( )

电客车主空压机启动压力（）bar.

我们在学习和生活中，常常看到下面的情形：

                      图1                                                    图2                                       图3                                   图4

（1）图1所示的是生活中常用的电能表，它的作用是测量________，示数是_________kW．h； 

（2）如图2所示，电压表表盘上的指针示数是_______V；

（3）如图3是某同学在研究通电螺线管极性时的情形， 请你在图中标出通电螺线管的N极；

（4）如图4所示，研究光的反射时，测得入射光线与镜面的夹角为40°．则反射角是_______度。

（本题的所有夹持仪器均已省略）请根据下图回答问题：

（1）图中仪器④⑤的名称：④_______，⑤_________。

（2）实验室制取氧气，某同学设计了图A的装置，并用仪器③收集氧气。其中，仪器①中盛放的试剂应为________，此法生成氧气的化学方程式为__________________，收集氧气的方法为___________。

（3）实验室制取二氧化碳，从B~G中选择仪器，组装发生装置，要求能方便控制反应的发生或停止，你的正确选择为（填字母）________，反应的化学方程式为________________。

（4）下图是氢气还原氧化铜的微型实验装置图。与上图A类比，眼药水瓶的作用相当于仪器（填仪器编号）__________。

For some time past,it has been widely accepted that babies—and other creatures—learn to do things because certain acts lead to “rewards(报酬)”,and there is no reason to doubt that this is true. But it used also to be widely believed that effective rewards, at least in the early time, had to be directly connected to such basic physiological(生理的) “drives” as thirst or hunger. In other words, a baby would learn if he got food or drink or some sort of physical comfort, not otherwise.

It is now clear that this is not so. Babies will learn to behave in ways that produce results in the world with no reward except success in sight.

Papousek began his studies by using milk in the normal way to “reward” the babies and to teach them to carry out some simple movements, such as turning the head to one side or the other.Then he noticed that a baby who had  had enough to drink would refuse the milk but would still go on making the learned response(回答) with clear signs of pleasure. So he began to study the children's responses in situations where no milk was provided. He quickly found that children as young as four months would learn to turn their heads to right or left if the movement “turned on” some lights—and indeed that they were able to learn some more turns to bring about(产生) this result,for example,two left or two right,or even to make as many as three turns to one side.

Papousek's light experiment was placed directly in front of the babies and he made the interesting observation that sometimes they would not turn back to watch the light closely although they would “smile and speak” when the light was on.Papousek concluded that it was not the sight of the lights which pleased them.It was the success they were achieving in solving the problem,in mastering the skill,and then there is a basic human nature to make sense of the world and bring it under control.

小题1:According to the writer,babies learn to do things which _______.

A．will satisfy their surprise

B．will meet their physical needs

C．are directly connected to pleasure

D．will bring them a feeling of success小题2:Papousek noticed in his studies that a baby _______.

A．would make learned responses when it saw the milk 

B．would continue the simple movements without being given milk 

C．would turn its head to right or left when it had enough to drink

D．would carry out learned movements when it had enough to drink 小题3:In Papousek's experiment babies make learned movements of the head in order to _______.

A．be praised

B．please their parents

C．be rewarded with milk

D．have the lights turned on 小题4:The babies would “smile and speak” at the lights because _______.

A．they succeeded in “turning on” the lights

B．the sight of lights was interesting

C．they need not turn back to watch the lights

D．the lights were directly connected to some basic “drives”

拱坝要求（）。

A.河谷断面的高宽比小

B.河谷断面的宽高比大

C.河谷断面的宽高比小

D.河谷断面的宽高比大于5