理想变压器原线圈接在如图所示的电压上,原副线圈匝数之比为10:1,串在原线圈上的

题型:多选题

问题:

理想变压器原线圈接在如图所示的电压上,原副线圈匝数之比为10:1,串在原线圈上的电流表的示数为1A,则以下叙述正确的是(  )

A.变压器输出功率为200W

B.若n1=100匝,则输出端线圈的磁通量变化率的最大值为2Wb/s

C.副线圈两端的电压表示数20V

D.变压器的输入功率是由发电厂的输出功率决定的

考点:变压器的结构和原理
题型:多选题

计算机网络按其所涉及范围的大小和计算机之间互联距离的不同,其类型可分为()。

A.局域网、广域网和万维网

B.局域网、广域网和国际互联网

C.局域网、城域网和广域网

D.广域网、因特网和万维网

题型:多选题

阅读下列短文,并做短文后的题目,从四个选项中,选出能回答所提问题或完成所给句子的最佳选项。

     Mr. Ellis is very old. He has seen many changes in his home town.

     He knows that things are different now. But he never forgets the old days. He likes to talk about them. He

often talks about his favourite birds, the robins (欧洲的一种小鸟). "When I was a boy, these houses were not

here. There were wide fields and tall trees. Every spring the robins would come. Thousands of them would fly

up to the north from the south. They spent the winter in the south. Some would build their nests (巢) in the trees

near our houses. Then people started to cut down trees, and they built more houses. The robins stopped coming.

They couldn't build their nests near our houses because there were no trees." 

     "Now there are too many houses and too many roads. There are no places for the robins. They do not come

any more."

1. Mr. Ellis often talks about _______. [ ]

A. his old house

B. the old days

C. his life now

D. his family

2. The birds, the robins, spent the winter in _______. [ ]

A. the south

B. the west

C. the north

D. the east

3. _______ built the nests in the trees. [ ]

A. Mr. Ellis

B. Some people

C. The robins

D. Some dogs

4. Then people ______ trees because they wanted to build more houses. [ ]

A. cut down

B. planted

C. bought

D. watered

5. From the pessage (短文) we can know that ______. [ ]

A. Mr. Ellis likes his new life now

B. there were many houses there in the old days

C. the robins can make their nests without trees

D. Mr. Ellis is not happy with the changes there

题型:多选题

城市维护建设税和教育费附加的税基为 ______。

A.资源税

B.营业税

C.土地使用税

D.所得税

题型:多选题

D


Doctor Seuss was born in 1904. By the middle 1950s, he had become one of the best-loved and most successful children’s book writers in the world. His books are very popular with young readers. They enjoy the invented words and the pictures of unusual funny animals and plants.
In 1954, Life magazine published(刊登) a report about school children who could not read. The report said many children’s books were not interesting. Doctor Seuss ply hoped to help children and decided to write books that were interesting and easy to read. He used words with the same ending sound, like fish and wish. He did not receive training in art. Yet, he drew the pictures for most of his books.
In 1957, Dr. Seuss wrote The Cat in the Hat. He used less than 230 words to write the book and even a six-year-old should be able to read it. It was a fun story and easy to read. Children loved it. Their parents loved it, too. Today it is still one of the stories they like best. The success of The Cat in the Hat made him want to write more books for children. In 1960, he wrote a book using less than fifty words. The book is called Green Eggs and Ham.
In 1984, Doctor Seuss won a Pulitzer Prize (普利策奖). He was honored for the education and enjoyment his books provided American children and their parents.
He died at the age of 87, but his influence remains. Millions of his books have been sold worldwide. People say his books helped change the way American children learned to read. Yet, his books are loved by people of all ages. Doctor Seuss once said. "I do not write for children. I write for people.\

People like his books because the books ______.

A.are cheap and easy to get

B.were written in different languages

C.are easy and interesting to read

D.were written with invented words

题型:多选题

()时间,南京国民政府中央政务委员会决定,将奉天省改名为辽宁省。

A.1928.6.4

B.1928.12.29

C.1929.1.27

D.1929.4.2

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