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问题 单项选择题 计算题

下图示意某小区域地形。图中等高距为100米，瀑布的落差为72米。据此完成下列小题。

图示区域的最大高差最接近（）

A.310米

B.360米

C.410米

D.560米

答案

参考答案：B

解析：

山峰海拔为580米，桥梁附近河岸所在地的海拔在200米～300米，且桥梁上游河段瀑布落差为72米，所以桥梁附近河岸与山峰的高差最接近360米。

考点：该题考查等高线地形图。

单项选择题

下列离子方程式正确的是（）。

A.选项A

B.选项B

C.选项C

D.选项D
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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.

1（）

A.like

B.as

C.for

D.with
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