在100个零件中,有一级品20个,二级品30个,三级品50个,从中抽取20个作为

题型:选择题

问题:

在100个零件中,有一级品20个,二级品30个,三级品50个,从中抽取20个作为样本.
①采用随机抽样法:抽签取出20个样本;
②采用系统抽样法:将零件编号为00,01,……,99,然后平均分组抽取20个样本;
③采用分层抽样法:从一级品,二级品,三级品中抽取20个样本;
下列说法中正确的是

A.无论采用哪种方法,这100个零件中每一个零件被抽到的概率都相等
B.①②两种抽样方法,这100个零件中每一个零件被抽到的概率都相等;③并非如此
C.①③两种抽样方法,这100个零件中每一个零件被抽到的概率都相等;②并非如此
D.采用不同的抽样方法,这100个零件中每一个零件被抽到的概率是各不相同的
考点:分层抽样简单随机抽样系统抽样
题型:选择题

诊断急性肺水肿最具有特征意义的依据是()。

A.严重的呼吸困难,发绀

B.心尖部舒张早期奔马律

C.交替脉

D.两肺干湿性啰音

E.严重呼吸困难伴咯粉红色泡沫样痰

题型:选择题

下列工具中属于需求分析常用工具的是______。

A.PAD

B.PFD 

C.N-S 

D.DFD

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I have a cousin who’s a farmer. If you saw him on market day with his old boots and worn hat, you might think he was a tramp (流浪汉). But he’s either buying or selling       for thousands of pounds. He doesn’t have a luxurious lifestyle, but the farmhouse, dozens of acres of land, machinery, cattle, chicken and crops must be worth a fortune. You might describe him as a       man, but he doesn’t look like that.
My father owned a shop selling newspapers, cigarettes, birthday cards, toys, books and magazines. The shop       a comfortable life for us, but we weren’t rich. The only luxury was that my father owned a car when most people in our town couldn’t afford one,      professionals such as doctors and lawyers.
My point is that       can be misleading. You often can’t       the rich from the way they look.
I once met Richard Branson, the Virgin Airlines tycoon (巨头).He’d       a hot balloon across the Atlantic and landed in the Irish sea. When he was rescued, he was wearing jeans, a T-shirt and a sneaker. You’d       have guessed he was a multimillionaire.
Andrew Bruce, the 11th Earl (伯爵) of Elgin,       a group of press people to his luxurious home in Fife, Scotland. His      , the 7th Earl of Elgin was famous for removing and transporting to Britain priceless sculptures from the Parthenon, a very famous temple in Greece. The so-called Elgin Marbles can be seen in the British Museum. The Earl’s castle was       cold, despite a fire burning in the hearth (壁炉). He explained to us,“I’m sorry it’s so cold, but you should know that a gentleman’s house is always cold.”
There you have it:     doesn’t always bring comfort.
小题1:
A.eggsB.foodsC.cattle D.fruits
小题2:
A.wealthyB.poorC.goodD.successful
小题3:
A.offeredB.providedC.suppliedD.gave
小题4:
A.besidesB.includingC.as well asD.apart from
小题5:
A.thingsB.factsC.appearancesD.faces
小题6:
A.sayB.tellC.recognizeD.judge
小题7:
A.madeB.drivenC.boughtD.flown
小题8:
A.perhapsB.neitherC.neverD.rather
小题9:
A.allowedB.permittedC.demandedD.invited
小题10:
A.forefatherB.fatherC.grandfatherD.father-in-law
小题11:
A.frozenB.freezingC.surprisingD.surprised
小题12:
A.healthB.wealthC.luckD.poverty
题型:选择题

对嵌压性神经病描述不正确的是()

A.正常时经过狭窄解剖通道的神经由于反复的缩窄性压迫导致脱髓鞘

B.临床表现似多发性神经炎

C.严重的压迫可有轴突变性

D.可服用非类固醇性抗炎药治疗

E.肌电图呈失神经支配为手术指征

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如果出现eNB的告警小区退服,光口不可用(1018007),可能是以下哪些原因造成的?()

A.主设备侧光模块损坏

B.RRU侧光模块损坏

C.主设备侧光模块型号不匹配

D.RRU侧光模块型号不匹配

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