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问题 选择题
下列说法错误的是（　　）
A．如果命题“￢p”与命题“p或q”都是真命题，那么命题q一定是真命题；
B．命题“若a=0，则ab=0”的否命题是：“若a≠0，则ab≠0”；
C．若命题p：∃x∈R，x2-x+1＜0，则¬p：∀x∈R，x2-x+1≥0；
D．“sinθ=
1
2
”是“θ=30°”的充分不必要条件
答案

解析：选项A：¬p为真，则p为假．又p或q为真，所以q为真命题．故A选项正确．

选项B：否命题将条件和结论交换，故B选项正确．

选项C：特称命题的否定为全称命题，∃换成∀，并且将结论变为否定形式，故选项C正确．

选项D：由sinθ=

1
2
可得θ=30°+K×360°，K∈Z．故应是必要不充分条件，所以选项D不正确．

单项选择题 A3型题

患者女，25岁。1型糖尿病患者，一直应用胰岛素治疗。2天前受凉后出现咳嗽、咳痰、发热，2小时前出现嗜睡、烦躁不安急诊入院。检查：体温38.7℃，脉搏132次／分，呼吸28次／分，皮肤干燥，呼吸深大，呼气有烂苹果味，心肺无异常，肝脾未触及。血糖33.3mmol/L，尿素氮20mmol／L，血钠140mmol／L，血钾4.2mmol／L，尿酮体（+++）。

该患者最可能出现的是（）

A.脑出血昏迷

B.尿毒症昏迷

C.乳酸酸中毒

D.糖尿病酮症酸中毒

E.低血糖昏迷
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单项选择题

The history of African—Americans during the past 400 years is traditionally narrated (1) an ongoing struggle against (2) and indifference on the part of the American mainstream, and a struggle (3) as an upward movement is (4) toward ever more justice and opportunity.

Technology in and of (5) is not at fault; it’s much too simple to say that gunpowder or agricultural machinery or fiber optics (6) been the enemy of an (7) group of people. A certain machine is put (8) work in a certain way—the purpose (9) which it was designed. The people who design the machines are not intent on unleashing chaos; they are usually trying to (10) a task more quickly, cleanly, or cheaply, (11) the imperative of innovation and efficiency that has ruled Western civilization (12) the Renaissance.

Mastery of technology is second only (13) money as the true measure of accomplishment in this country, and it is very likely that by (14) this under-representation in the technological realm, and by not questioning and examining the folkways that have (15) it, blacks are allowing. (16) to be kept out of the mainstream once again. This time, however, they will be (17) from the greatest cash engine of the twenty-first century. Inner-city blacks in particular are in danger, and the beautiful suburbs (18) ring the decay of Hartford, shed the past and learn to exist without contemplating or encountering the tragedy of the inner city.

And blacks must change as well. The ways that (19) their ancestors through captivity and coming to freedom have begun to loose their utility. If blacks (20) to survive as full participants in this society, they have to understand what works now.

7（）

A.entirely

B.enter

C.entire

D.entrance
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