搜题请搜索小程序“爱下问搜题”
问题 单项选择题 A1/A2型题

增感屏的结构中不包括（）

A.荧光体层

B.保护层

C.片基层

D.反射层

E.基层

答案

参考答案：C

解析：增感屏的结构包括：①基层；②荧光体层；③保护层；④反射层或吸收层。并没有片基层，要注意不能与胶片混淆。

问答题

Americans are much more likely than citizens of other nations to believe that they live in a meritocracy, i.e. Government by people selected according to merit. But this self-image is a fantasy: America actually stands out as a the advanced country in which it matters most who your parents were, the country in which those born on one of society’s lower rungs have the least chance of climbing to the top or even to the middle.　　And if you ask why America is more class-bound in practice than the rest of the Western world, a large part of the reason is that our government falls down on the job of creating equal opportunity.　　The failure starts early: in America, the holes in the social safety net mean that both low-income mothers and their children are all too likely to suffer from poor nutrition and receive inadequate health care. It continues once children reach school age, where they encounter a system in which the affluent send their kids to good, well-financed public schools or, if they choose, to private schools, while less-advantaged children get a far worse education.
查看答案
单项选择题

厂内机动车辆驾驶员不从事驾驶工作（除担任车管工作外）（）者，须继续担任驾驶工作时，应重新考核。

A、3个月

B、6个月

C、1年

D、2年
查看答案