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问题 填空题

在△ABC中，AB=AC，若要使△ABC是等边三角形，那么需添加一个条件：______或______（从不同角度填空）．

答案

要使△ABC是等边三角形，从边考虑：可以添加的条件为AB=AC或AC=BC，

从角考虑：可以添加的条件为∠A=60°或∠B=60°或∠C=60°．

所以可以添加的条件是AB=AC或∠A=60°．

故答案为：AB=AC或∠A=60°（答案不唯一）．

单项选择题

船舶共有人就共有船舶设定抵押权，应当取得持有（）以上份额的共有人的同意。

A.三分之一

B.二分之一

C.四分之一

D.三分之二
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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.

5（）

A.itself

B.themselves

C.ourselves

D.himself
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