氧气和二氧化碳是空气的两种组成成分。下列叙述正确的是 A．O2是人体生命活动不可

Many companies use guards and expensive alarm systems to protect their property (财产). Soon a new kind of protection will be used—robots. Engineers have been working on the first mobile robots for businesses. The robots will guard factories, warehouses (仓库) and museums at night.

The mobile robots will move around slowly on wheels. They will be able to detect (察觉,发现) people through walls and pick up sounds, such as breaking glass. They can be fixed with loud sirens to frighten thieves, or radios to signal police or guards.

To protect a building, a robot will have to move around without knocking into the walls. Information about the building will have to be stored in the robot’s small, built-in computer. A floor map could be programmed into the computer’s memory, for example.

A mobile robot will not be able to do everything. Unlike human guards, it will not be able to climb stairs, open doors, or move along rough ground. It won’t be able to tell the difference between friends and enemies. Because of that, people will have to be prevented from entering the area it moves.

One kind of mobile robot will be able to “sense” whether a chair or a box has been moved and go around it. This robot will also judge size well enough so that it won’t send an alarm if a cat crosses the room. And if someone tries to steal this robot, it will sound a loud, painful siren. The three-foot-tall robot is hard to be stolen anyway. It weighs about 200 pounds.

U.S. companies pay almost $10 billion a year to protect their property with alarm systems and human guards. Mobile robots may be cheaper.  (296)

小题1: Why is the new kind of robots called mobile robots? Because they can _____.

A．guard factories, warehouses and museums

B．send loud, painful sirens when it is stolen

C．sense moving objects and signal police

D．move around and do the programmed work小题2: How will a robot get directions for moving around a building?

A．From a human guard.

B．From a built-in computer.

C．From another robot.

D．From radio signals.小题3: What can be the best title of this passage?

A．New Guards.

B．Science and Technology.

C．Alarm Systems.

D．Engineers and Robots.

有的物质是由______构成的，如水______，______等，有些物质是由______构成的，如铁______等，有些物质是由______构成的，如______等．

有关人体内环境稳态的叙述，错误的是[ ]

A．有3种以上的生理系统参与维持体内环境稳态

B．人体内环境稳态的失调与外界环境无关

C．人体维持内环境稳态的调节能力有限

D．稳态有利于参与其调节的器官保持机能正常

在实施16PF测验时，应当记住的是（）。

A.每题只能选择一个答案

B.不可漏掉任何测题

C.尽量不选择中性答案

D.对于不太容易回答的试题，同样要求被试者作出一种倾向性选择

( )脑血管意外恢复期老人在练习站立位时，身体应向前倾斜才能达到直立位。