家用门铃、电推子禁止用220V电源电压,应使用()以下的安全电压 A.36V B.4

题型:单项选择题

问题:

家用门铃、电推子禁止用220V电源电压,应使用()以下的安全电压

A.36V

B.48V

C.6V

考点:家庭安全知识竞赛居家安全知识竞赛居家安全知识竞赛题库
题型:单项选择题

电梯消防返回基站开关动作后().

A.已开启轿门的电梯,将轿门关闭后,即返基站

B.正在运行的电梯,就 * * 层后,不开门,即返基站

C.返回基站后开门

D.下行过程中,将要下行的人员接到基站

题型:单项选择题

Once there was an old man in a town. He always forgot a lot of things. So his wife always had to say to him, “Don’t forget this!”

One day he went on a long trip alone. Before he left home, his wife said, “Now you have all these things. They are what you need for your trip. Take care of your things during the trip.” He went to the station, bought a ticket and got on the train with it.

About half an hour later, the conductor began to see the tickets. He came to the old man and said, “Will you please show me your ticket?” The old man looked for his ticket in all his pockets, but he could not find it. He was very worried. “I can’t find my ticket. I really bought a ticket before I got on the train.”said the old man.

“I believe you bought a ticket. All right, you don’t have to buy another one,”said the conductor kindly. “But how can I know where I’m going? I can’t remember my station!”the old man said sadly.

(    )1.The old man in the story was very___________.

A. kind      B. poor     C. forgetful   D. sad

(    )2.Where is the ticket?            

A. The old man forgot go buy it.

B. The old man could not remember where it was.

C. The old man showed it to the conductor.

D. The old man’s wife took the ticket away.

(    )3.The old man bought the ticket ________ he got on the train.

A. after       B. before       C. as        D. when

(    )4.The conductor __________  the old man.

A. didn’t believe  B. laughed at   C. believed    D. felt sorry for

(    )5. The old man was sad because             

A. he had to buy another ticket.

B. he lost all the things his wife gave him.

C. he did not know where he was.

D. He did not know where he should get off.

题型:单项选择题

为了加快液体的蒸发,可以______液体的温度,______液体的表面积和______液体表面上气体的流动.

题型:单项选择题

如果课程编制者认为课程内容是儿童的学习经验,那么他们在选择课程内容时,必然会()。

A.关注幼儿园环境的创设

B.注重使课程内容与儿童发展特征相符合

C.较多考虑知识本身的系统性和逻辑性

D.强调教师的事先预设

题型:单项选择题

以下对MAC地址描述正确的是()

A、由32位2进制数组成

B、由48位2进制数组成

C、前6位16进制由IEEE负责分配

D、后6位16进制由IEEE负责分配

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