搜题请搜索小程序“爱下问搜题”
问题 单项选择题

《建筑消防安全检测评价技术规程》规定，工作接地电阻：专用接地电阻值应（），公用接地时，接地电阻值应（）

A.≥4Ω，≥1Ω

B.≤4Ω，≤1Ω

C.≥1Ω，≥4Ω

D.≤1Ω，≤4Ω

答案

参考答案：B

多选题

如图所示，物体A在竖直向上力F的作用下静止在斜面，则（　　）

A．物体A可能受两个力作用

B．物体A可能受四个力作用

C．若保持力F方向不变，大小逐渐增大，则摩擦力的大小一定增大

D．若保持力F方向不变，大小逐渐增大，则摩擦力的大小可能先减小后增大
查看答案
单项选择题

"Culture shock" occurs as a result of total immersion in new culture. It (51) to "people who have been suddenly transplanted abroad. " Newcomers may be anxious (52) they do not speak the language, know the (53) , or understand people’s behavior in daily life. The visitor finds that "yes" may not always mean "yes", that friendliness does not (54) mean friendship or that statements that appear to be serious are really intended (55) jokes. The foreigner may be unsure as to when to shake hands or embrace, when to (56) conversations, or how to approach a stranger. The (57) . of "culture shock" helps explain feelings of bewilderment and disorientation. Language problems do not account for all the frustrations that people feel. When one is (58) of everything that was once familiar, such as understanding a transportation system, knowing how to register for university classes, (59) knowing how to make friends, difficulties in coping with the new society may (60) .

59（）。

A. but

B. nor

C. or

D. and
查看答案