《蒿里行》描写了（）时期的惨景：“白骨露于野，千里无鸡鸣。”被后人誉为“汉末实录”。

阅读短文，选择正确答案。

    Although cliff diving may bring great excitement, it's a very dangerous sport that people should be careful

about. It is completely wrong to think that the diver is cushioned (缓冲) by the water below-this could not be

further from the truth. When jumping from a cliff that is over 70 feet high, a diver hits the water at over 46 mph

(miles per hour). Such high speeds make the point of contact feel like a wall, so the diving skills are very

important. 　　

    Professional divers are trained and well-prepared to make dives. However, non-professionals should never

dive because a diver's body position (体位) at the time of contacting water is very important to his or her safety.

Because of the great danger, divers should always seriously think about their skills before trying any moves. 　　

    Although there is no truly safe way to jump off a cliff, non-professional divers are encouraged to pencil dive.

To do a pencil dive, the jumpers leap their feet first off the cliff, keep arms at their sides with legs together and

pointing downward. The diver should keep the body tight and vertical (垂直的). This is safer because it makes

the point of contact smaller when the diver enters the water and puts less stress (压力) on the body. 　　

    Wearing a wet suit while diving will result in less pain. So it is wise for new divers to wear wet suits. But

professional divers suggest staying away from water shoes. Although wearing shoes might seem like a good

idea, they actually increase the force of impact(冲击力) because they increase the surface area of the diver at

impact. The increased force of impact puts stress on a diver's body and can lead to broken bones. Without a

doubt, diving without shoes is the safer way to go. 　　

    Besides the height, speed, water depth and body position, it is also important for divers to make wise

decisions when they are thinking about diving. Cliff diving tests both a person's physical and mental(心理的)

skills, so it is never a good idea to jump with a sudden idea. A person needs to be of sound mind and in good

health to even think about a dive. One should never try a dive if he has drunk wine. What's more, a person

should never make someone who is not feeling 100% confident dive.

1. What does "this could not be further from the truth" mean? [ ]

A. There's no doubt that this idea is definitely true. 　　

B. This idea is thought to be completely wrong. 　　

C. It depends on the real situation on the spot. 　　

D. Nobody knows whether this idea is true or not.

2. Why didn't professional divers suggest wearing shoes? Because wearing shoes can             . [ ]

A. put more weight on to the diver 　　

B. cause the diver to feel uncomfortable 　　

C. make the point of contact bigger 　　

D. certainly lead to broken bones

3. According to the passage, a good cliff diver should be _______. [ ]

A. well-prepared and skillful　　　　

B. professional and strong 　　

C. creative and smarty 　　　　　　　

D. confident and brave

Although he has _____ physical disability, he has _____ ability to do the job.[ ]

A. the, the

B. a, a

C. the, a

D. a, the

如图为“用DIS（位移传感器、数据采集器、计算机）研究加速度和质量的关系”的实验装置．

（1）在该实验中采用控制变量法，应保持______不变，用DIS测小车的加速度，小车上安装的是位移传感器的______部分．

（2）（单选题）改变小车的总质量M，多次重复测量．在某次实验中根据测得的多组数据可画出a-QUOTE 关系图线如图所示．此图线的cd段明显偏离直线，造成此误差的主要原因是______

（A）小车与轨道之间的摩擦力越来越大

（B）导轨处于水平状态

（C）所挂钩码的质量太小

（D）所用小车的总质量太小．

双 * * 当期返奖占总销售额的（）

A、30%

B、50%

C、70%

D、90%

适龄少年