两个面积相等的平行四边形，它们的形状（ ） A．不相同 B．相同 C．不一定相同

在测定小灯泡的功率”的实验中，小明所在的实验小组要测量一只额定电压为3.8V的小灯饱的功率．

（1）如图甲所示，为实验小组未完成的实物电路，请用笔画线代替导线完成实物电路的连接；并根据实物连接图，在上右虚线框中用规定的电路符号画出相应的电路图．

（2）连好电路后，闭合开关，电压表的示数为3V时电流表的示数为0.27A，小灯泡的实际功率为______W；调节滑动变阻器的滑片使小灯饱正常发光，电流表的指针位置如图乙所示，则小灯泡的额定功率为______W．

一传送带装置示意如图，其中传送带经过AB区域时是水平的，经过BC区域时变为圆孤形（圆孤由光滑模板形成，未画出），经过CD区域时是倾斜的，AB和CD都与BC相切。现将大量的质量均为m的小货箱一个一个在A处放到传送带上，放置时初速为零，经传送带运送到D处，D和A的高度差为h。稳定工作时传送带速度不变，CD段上各箱等距排列，相邻两箱的距离为L。每个箱在A处投放后，在到达B之前已经相对于传送带静止，且以后也不再滑动（忽略经BC段时的微小滑动）。已知在一段相当长的时间T内，共运送小货箱的数目为N。这装置由电动机带动，传送带与轮子间无相对滑动，不计轮轴处的摩擦。求电动机的平均输出功率P。

下列各句中，标点符号使用正确的一句是(      )

A．教师认真地改，学生认真地学；教师爱护学生，学生尊敬老师，师生关系非常融洽。

B．什么是说明文的科学性呢？就是如实地反映客观事物，反映正确就是客观的。反之，就是不科学的。

C．俗话说“到什么山唱什么歌”，又说“看菜吃饭，量体裁衣。”我们无论做什么事都要看情形办理，写文章和演说也是这样。

D．落实以人为本，全面、协调、可持续发展的科学发展观，切实为人民创造良好的生产、生活环境，是我们每个党员应尽的职责。

Photographs are everywhere. They decorate (装饰) the walls of homes and are used in stores for sales of different goods. The news is filled with pictures of fires, floods, and special events. Photos record the beauties of nature. They can also bring things close that are far away. Through photos, people can see wild animals, cities in foreign lands, and even the stars in outer space. Photos also tell stories.

Reporting the news through photos is called photojournalism. At times photojournalists tell their stories through a single picture. At other times, they use a group of pictures to tell a story. Each picture is like a chapter in a book, which can do more than record the facts. It can also be a strong force for social change.

Jacob Riis was among the first photojournalists. He took pictures of parts of New York City where the poor lived. Riis believed that poverty(贫穷)　caused crime, and he used photos to help him prove his point. A few years later, the photos of small children working in factories by Lewis Hine shocked the public. Hine’s pictures helped bring about laws to protect such children.

Hundreds of pictures may have to be taken in order to get one or two really good photos. It takes science to have the photo come out clearly and art to make a photo that has a good design and expresses feeling. Photojournalists make an actual record of what they see. A photo, however, can be both a work of art and an actual record. It can record an important event as a beautiful or exciting picture.

As historical and artistic documents(文献) ,photos can become more important over time. Today photojournalists still have their pictures appear in newspapers and magazines. They also publish(发表) them in books and on the Internet.

小题1:The underlined word “They” in the first paragraph refers to        .

A．beauties

B．photos

C．goods

D．events小题2:The photos of the small children by Hine show us that photos           .

A．are also works of art

B．are popular ways of reporting news

C．often shock the public

D．can serve as a force for social change小题3:What can we learn from the passage?

A．News with pictures is encouraging.

B．Photos help people improve

C．News photos mean history in a sense.

D．People prefer reading news with pictures.小题4:The text is mainly about      .

A．telling the story through picture

B．decorating the walls of homes

C．publishing historical papers

D．expressing feeling through pictures

某一固定观念在脑子里反复出现，患者无法摆脱这一观念而感到痛苦并求医，这属于（）