R1和R2两只电阻并联在电路中,通过R1的电流和通过R2的电流比为2:3,则R1

题型:选择题

问题:

R1和R2两只电阻并联在电路中,通过R1的电流和通过R2的电流比为2:3,则R1:R2为(  )

A.2:3

B.3:2

C.1:1

D.无法确定

考点:欧姆定律及其应用并联电路的电压规律
题型:选择题

有机磷中毒时应用阿托品,下列哪项是错误的()

A.用量应根据病情适当使用

B.达到阿托品化后减少阿托品的剂量或停用

C.与胆碱酯酶复活剂合用时,阿托品的剂量应减少

D.重度中毒时应静脉给药

E.当出现阿托品中毒时应立即间隔给药

题型:选择题

阅读理解(共20小题; 每小题2分,满分40分)

阅读下列短文,从每题所给的四个选项(A、B、C和D)中,选出最佳选项。

I felt encouraged by his words and began to swim more calmly.But my clothes stuck to me like a heavy weight.I could hardly stay above the surface.

Counsel saw this.“Shall I cut them?”he asked.

With a knife he cut my clothes from top to bottom and took them of quickly while I swam for both of us.

Then I did the same for Counsel,and we continued to swim near each other.

But we were in serious trouble.The crew(船员)might not have noticed our disappearance.

And if they had,they could not return because the rudder(舵)had broken.Counsel thought of all this,and calmly made his plans.We decided to wait for the ship as long as possible,because we had no other hope of safety.I suggested that we save our strength so that both of us would not be tired out at the same time.This was how we did it:While one of us lay on his back,quite still,with arms crossed and legs stretched out(伸直),the other would swim and push him along.We changed every ten minutes or so.In this way we could swim for hours,perhaps till daylight.The crash(破裂声)of the ship and the whale(鲸)had appeared at about eleven o’clock.We had about eight hours to swim before daylight.This seemed possible,if the sea remained calm.

小题1:What happened to the man who told the story?

A.He and his companion got into the water to test their strength.

B.He jumped into the water to save the broken rudder.

C.He was knocked into the water by his enemy.

D.He was thrown into the sea when the ship struck a whale.小题2:Why did the two men cut their clothes?

A.Because no people helped them to take off their clothes.

B.Because they couldn’t take off their clothes on the sea.

C.Because they wanted to get rid of their clothes quickly.

D.Because they wanted to lifebuoys(救生圈)with their clothes.小题3:What does the word “still” in the last paragraph mean?

A.not moving

B.even

C.yet

D.however小题4:n order to save their strength,______.

A.one of them pushed the other while swimming and then they changed

B.they both swam calmly

C.they crossed their arms and stretched their legs on the water

D.they lay on their backs instead of swimming小题5:Which one of the following is true?

A.Neither of the two men was good swimmers.

B.The sea was calm before eleven o’clock that night.

C.The story took place at night.

D.The two men had to swim eight hours to catch up with the ship.

题型:选择题

对于借款企业来讲,若预测市场利率上升,应与银行签订浮动利率合同;反之,则应签订固定利率合同

题型:选择题

慢性单纯性鼻炎与慢性肥厚性鼻炎相鉴别的主要依据是()

A.鼻塞的严重程度

B.鼻腔分泌物的黏稠程度

C.鼻甲粘膜的肥厚程度及对血管收缩剂的反应

D.是否并发慢性咽炎

E.病程时间的长短

题型:选择题

为什么说全及指标是唯一确定的量,而抽样指标则是一个随机变量?

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