| There are some earth phenomena you can
count on, but the magnetic field, some say, is not one of them. It fluctuates in
strength, drifts from its axis, and every few 100,000 years undergoes a dramatic
polarity reversal -- a period when north pole becomes south pole and south pole
becomes north pole. But how is the field generated, and why is it so
unstable Research by two French geophysicists promises to shed some light on the mystery. Using 80 meters of deep sea sediment (沉淀物), they have obtained measurements of magnetic-field intensity that span 11 polarity reversals and four million years. The analysis reveals that intensity appears to fluctuate with a clear, well-defined rhythm. Although the strength of the magnetic field varies irregularly during the short term, there seems to be an inevitable long-term decline pre A. It means to "decline". B. It means to "fluctuate". C. It means to "intensify". D. it means to "reverse". [单选题]变压器套管等瓷质设备，当电压达到一定值时，这些瓷质设备表面的空气发生放电，叫做（）。
A.气体击穿 B.气体放电 C.沿面放电 D.瓷质击穿 [判断题]《南昌局集团公司安检查危工作管理办法》（南铁客〔2019〕264号）规定公安机关作为国家行政执法力量，对集团公司安检查危工作具有监督、检查、指导和执法权，各单位和安检人员应积极配合自觉接受铁路公安机关的监督、检查、指导。
A.正确 B.错误 [判断题] 工器具管理模块中工器具送检流程无需闭环。
A.正确 B.错误 [单选题]回热循环效率的提高一般在( )。
A.10%； B.18%； C.20%～25%； D.大于25%。 [单项选择]硬关井是在（）状态下，强行关闭防喷器的操作程序。
A. 节流及放喷闸门关闭 B. 节流闸门打开，放喷闸门关闭 C. 节流及放喷闸门打开 D. 节流闸门关闭，放喷闸门打开 [简答题]妊娠剧吐病人出现什么情况，应考虑终止妊娠？
[单项选择]A cold dish of raw vegetables with a dressing is called ______.
A. hamburger B. sandwich C. salad D. pudding [单选题]测量并调整刚柔过渡非入槽接触线下锚前悬挂点拉出值使其符合设计值，允许误差±（）mm
A.5 B.10 C.20 D.30 [单选题](45151)Ⅱ级铁路,在路网中起骨干作用或在路网中起联络、辅助作用,近期年客货运量( )。(1.0 分)
A.≥20Mt B.≥10Mt且<20Mt C.≥5Mt且<10Mt D. 、 <5Mt [单选题]手信号显示昼间右臂向右平伸，左臂下垂；夜间白色灯光作圆形转动后，再上下摇动是()股道。
A.五 B.六 C.七 D.八 [判断题]更名是原客户不变，只是因客户原名称改变而变更客户名称的业务。
A.正确 B.错误 我来回答: 提交
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