两个相同的白炽灯泡L1和L2接到如图1所示的电路中,灯L1与电容器串联,灯L2与

题型:选择题

问题:

两个相同的白炽灯泡L1和L2接到如图1所示的电路中,灯L1与电容器串联,灯L2与电感线圈串联.当a、b间接电压最大值为Um、频率为f的正弦交流电源时,两灯都发光,且亮度相同.更换一个新的正弦交流电源后,灯L1的亮度低于灯L2的亮度.新电源两极的电压最大值和频率可能是                (  )

A.最大值仍为Um,而频率大于f

B.最大值仍为Um,而频率小于f

C.最大值大于Um,而频率仍为f

D.最大值小于Um,而频率仍为f

考点:电感器对交变电流的作用电容器对交变电流的作用
题型:选择题

肾衰竭多尿期治疗中,下列说法不正确的是()。

A.血K+,BUN,Cr仍有可能升高

B.按生理需要量补充K+

C.要注意消化道出血的防治

D.重视营养支持

E.控制感染

题型:选择题

补全对话:根据对话内容,从对话后的选项中选出能填入空白处选出最佳选项。选项中有两项为多余选项。

—Have you eve.

—Yes. We just studied cloning last week.

—1._____?

—Of course. It’s very interesting

—I would clone myself.

—2._____?

—Yes. My clone could do many things for me.

—I don’t think so. 4._____.

—Then I would clone a king. I want to see a real king.

—But all the kings are dead. 5._____.

—Then I don’t know what to clone.

A. Maybe I will become a scientist and clone a new animal

B. If you were a scientist, what would like to clone

C. It's impossible for us to clone a dead man

D. If you had a clone, nobody could tell you and your clone apart

E. Do you think it’s a good idea

F. We saw a movie about cloning

G. Are you interested in it

题型:选择题

生产中药饮片须按照药品标准及省、自治区、直辖市人民政府药品监督管理部门制定的炮制规范炮制。()

题型:选择题

()的现象属于感觉适应。

A.入芝兰之室久而不闻其香

B.电灯灭了,眼睛里还会看到亮着的灯泡的形状

C.从亮出到暗处,开始看不到东西,要过一段时间才能看到

D.绿叶陪衬下的红花看起来更红了

题型:选择题

从几何上看,詹森指数表现为基金组合的实际收益率与SML直线上具有相同风险水平组合的期望收益率之间的偏离。( )

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