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问题 单项选择题

魏晋南北朝时期，我国冶金技术取得的最重要成就是（）

A.鎏金术

B.水排

C.灌钢法

D.铸钢法

答案

参考答案：C

解析：联系所学知识可知，南北朝时期，出现了灌钢法，直到16世纪以前中国炼钢技术领先世界，故此题应选C项

单项选择题

某工程投标出现下列情形，评标委员会应当否决的投标是（）。

A.甲公司的报价超过标底的上浮范围

B.乙公司的报价超过标底的下浮范围

C.丙公司的报价高于招标文件设定的最低投标限价

D.丁公司的报价低于成本
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单项选择题

Fossils of the coral Aerocora palmata that date from the last period when glaciers grew and consequently spread from the polar regions are found at ocean depths far greater than those at which A. palmata can now survive. Therefore, although the fossilized A. palmata appears indistinguishable from A. palmata now living, it must have differed in important respects to have been able to live in deep water.
The argument depends on the assumption that

A．no fossils of the coral A. palmata have been found that date from periods when glaciers were not spreading from the polar regions.

B．geological disturbances since the last period during which glaciers spread have caused no major downward shift in the location of A. palmata fossils.

C．palmata now live in shallow waters in most of the same geographical regions as those in which deep-lying A. palmata fossils have been found.

D．patlmata fossils have been found that date from each of the periods during which glaciers are known to have spread from the polar region.

E．(E) A. palmata can live at greater depths where the ocean temperature is colder than they can where the ocean temperature is warmer.
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