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问题 选择题

下列都属于鱼类的一组动物是（　　）

A．比目鱼、带鱼、鳄鱼

B．鲳鱼、娃娃鱼、鳙鱼

C．金鱼、草鱼、海马

D．鲢鱼、鱿鱼、墨鱼

答案

真正属于鱼类要具备鱼类的基本特征，

A、鳄鱼体表有鳞片，用肺呼吸，卵生，是爬行动物，比目鱼、带鱼生活在水中用鳃呼吸，用鳍来游泳属于鱼类，故不符合题意；

B：娃娃鱼、幼体用鳃呼吸，成体用肺呼吸，属于两栖动物；鲳鱼、鳙鱼生活在水中用鳃呼吸，用鳍来游泳是鱼类．故不符合题意；

C：金鱼、草鱼、海马，生活在水中用鳃呼吸，用鳍来游泳，属于鱼类．故符合题意；

D：鱿鱼、墨鱼甲鱼无脊柱，身体柔软、有外套膜属于软体动物；鲢鱼生活在水中用鳃呼吸，用鳍来游泳是鱼类，故不符合题意．

故选C．

单项选择题

接触角可表示（）

A.粉体流动性 

B.粉体润湿性 

C.水溶性粉体的吸湿性 

D.粉体粒子大小 

E.粉体的压缩性
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单项选择题

Comparisons were drawn between the development of television in the 20th century and the diffusion of printing in the 15th and 16th centuries. Yet much had happened between. As was discussed before, it was not until the 19th century that the newspaper became the dominant pre- electronic (61) , following in the wake of the pamphlet and the book and in the (62) of the periodical. It was during the same time that the communications revolution (63) UP, beginning with transport, the railway, and leading on through the telegraph, the telephone, radio, and motion pictures into the 20th-century world of the motor car and the air plane. Not everyone sees that process in (64) . It is important to do so.

It is generally recognized, (65) , that the introduction of the computer in the early 20th century, (66) by the invention of the integrated circuit during the 1960s, radically changed the process, although its impact on the media was not immediately (67) . As time went by, computers became smaller and more powerful, and they became "personal" too, as well as (68) , with display becoming sharper and storage (69) increasing. They were thought of, like people, (70) generations, with the distance between generations much (71) .

It was within the computer age that the term "information society" began to be widely used to describe the (72) within which we now live. The communications revolution has (73) both work and leisure and how we think and feel both about place and time, but there have been (74) view about its economic, political, social and cultural implications. "Benefits" have been weighed (75) "harmful" outcomes. And generalizations have proved difficult.

（66）是（）

A.brought

B.followed

C.stimulated

D.Characterized
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