当外部时间基准信号从消失到恢复时,标准时间同步钟本体和时标信号扩展装置应自动切换到正

题型:单项选择题

问题:

当外部时间基准信号从消失到恢复时,标准时间同步钟本体和时标信号扩展装置应自动切换到正常状态工作,切换时间应小于()s。

A.0.1

B.0.2

C.0.5

D.1

考点:继电保护工考试继电保护中级工继电保护中级工题库
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已知点P(-2,1),Q(3,2),直线l过点M(0,1)且与线段PQ相交,则直线l的斜率K的取值范围是______.

题型:单项选择题

In 1879, a group of explorers made an incredible find. They discovered paintings of remarkable beauty on the walls of a cave in Spain. Some scientists believed that these paintings were created by early humans from the Stone Age, between ten and thirty thousand years ago. Other scientists and the public did not believe the claim, but over the years, it was proven correct. Our ancestors had incredible artistic talents.

Most of the cave art that has been discovered has been found in Spain and France. A smaller number of such caves are located in Italy, Portugal, Russia, and other countries. Scientists believe that many more caves will be discovered in the coming years, and are concentrating their efforts on Africa and the area between Europe and Asia. These two regions of the world were, populated first by humans.

Cave art was carved or painted on the walls and roofs of caves, usually near the entrance. The entrance area was probably chosen to take advantage of daylight and to allow many people to view the paintings. In some cases, the art appears much deeper in caves and requires artificial light. Evidence suggests that the artists used torches or shallow bowls in which animal fat was burned.

9.What was the response of general public to the discovery of cave art made by Stone Age people?

A. They believed it at first.

B. They did not believe it.

C. They thought it was beautiful.

D. They ignored it.

10.According to the passage, what can we conclude about animal fat?

A. It does not burn.

B. Stone Age artists used it to preserve their paintings.

C. It can be burned to produce light.

D. Stone Age artists mixed it with their food.

11.. Where do scientists expect to find more cave paintings?

A. In Central and South America.

B. In Spain and France.

C. In the places where there are caves with large openings.

D. In the regions of the world first populated by humans.

12.Where would this passage be most likely to appear?

A. In a textbook about early human history.

B. In a textbook about modern art.

C. In a dictionary.

D. In an encyclopedia entry about caves.

题型:单项选择题

高速(客)船在离港前及整个航行时间内,只要大部分救生设备处于正常状态就行了。

题型:单项选择题

现行的建筑工程施工质量验收规范体现了()的指导思想。

A.验评分离

B.标准统一

C.强化验收

D.过程控制

E.完善手段

题型:单项选择题

根据《计算机保护条例》的规定,软件持有者不知道或没有合理的依据知道该软件是侵权物品,其侵权责任由()承担

A.该侵权软件的提供者

B.该侵权软件的持有者

C.计算机软件的最终用户

D.软件的提供者和持有者共同

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