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问题 单项选择题

下列关于复叠式制冷循环说法错误的是（）

A.复叠式制冷循环通常由两个或两个以卜不同制冷剂工作的单级（或多级）制冷系统组合而成

B.复叠式制冷循环通常在低温系统使用沸点较高的制冷剂，而在高温系统使用沸点较低的制冷剂

C.高温部分系统中制冷剂的蒸发是用来冷凝低温部分系统中的制冷剂

D.低温部分系统中的制冷剂在蒸发时从被冷却对象吸热

答案

参考答案：B

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 (91) . As was discussed before, it was not (92) the 19th century that the newspaper became the dominant pree-leetronie (93) , following in the wake of the pamphlet and the book and in the (94) of the periodical. It was during the same time that the communications revolution (95) up, beginning with transport, the railway, and leading (96) through the telegraph, the telephone, radio, and motion pictures (97) the 20th-eentury world of the motor ear and the airplane. Not everyone sees that process in (98) . It is important to do so.
It is generally recognized, (99) , that the introduction of the computer in the early 20th century, (100) by the invention of the integrated circuit during the 1960s, radically changed the process, (101) its impact on the media was not immediately (102) . As time went by, computers became smaller and more powerful, and they became "personal" too, as well as (103) , with display becoming sharper and storage (104) increasing. They were thought of, like people, (105) generations, with the distance between generations much (106)
It was within the computer age that the term" information society" began to be widely used to describe the (107) within which we now live. The communications revolution has (108) both work and leisure and how we think and feel both about place and time, but there have been (109) views about its economic, political, social and cultural implications. "Benefits" have been weighed (110) "harmful" outcomes. And generalizations have proved difficult.

A．between

B．before

C．since

D．later
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单项选择题

炎症性急腹症的特点不包括

A．腹疼由轻到重

B．持续性腹疼

C．病变部位固定压疼

D．腹膜炎范围不随病变加重而扩大

E．常伴有发热等症状
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