有关雷达荧光屏匕船首线位置影响测方位误差大小的下述说法中()是错的。A.船首线出现的

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问题:

有关雷达荧光屏匕船首线位置影响测方位误差大小的下述说法中()是错的。

A.船首线出现的时间应该是天线主波束转过船首的时间

B.船首线宽度应不大于0.5°

C.在船首向上显示方式中,扫描中心在屏中心时,船首线应对准固定方位盘0°

D.在真北向上显示方式中,不管扫描中心在屏上哪个位置,船首线均应指向固定方位盘上的航向值

考点:海船船员考试雷达雷达题库
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不透明的口袋里装有白、黄、蓝三种颜色的乒乓球(除颜色外其余都相同),其中白球有2个,黄球有1个,现从中任意摸出一个白球的概率是(    ),则口袋里有蓝球(    )个。

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计算:(a32+a5的结果是     

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酗酒引起急性胰腺炎是因为

A.引起胆囊收缩

B.刺激胰腺分泌旺盛

C.引起十二指肠炎、 * * 水肿

D.Oddi括约肌痉挛

E.引起胰管水肿

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阅读理解。

     Cassandra Feeley finds it hard to manage on her husband's income So this year she did something more

than a hobby (业余爱好): She planted vegetables in her yard. For her first garden, Ms Feeley has put in 15

tomato plants, and five rows of a variety of vegetables. The family's old farm house has become a chicken

house, its residents arriving next month. Last year, Ms Rita Gartin kept a small garden. This year she has

made it much larger because, she said, "The cost of everything is going up and I was looking to lose a few

pounds, too; so it's a win-win situation all around."

     They are among the growing number of Americans who, driven by higher living costs and a falling

economy(经济), have taken up vegetable gardening for the first time. Others have increased the size of their

existing gardens. Seed companies and garden shops say that not since the 1970s has there been such an

increase in interest in growing food at home. Now many gardens across the country have been sold out for

several months. In Austin, Tex, some of the gardens have a three-year waiting list.

     George C. Ball Jr. owner of a company, said sales of vegetable seeds and plants are up by 40% over last

year, double the average growth of the last five years. Mr. Ball argues that some of the reasons have been

building for the last few years. The big one is the striking rise in the cost of food like bread and milk, together

with the increases in the price of fruits and vegetables. Food prices have increased because of higher oil price.

People are now driving less, taking fewer vacations, so there is more time to garden.

1. What does the word "residents" in Paragraph 1 probably refer to?

A chickens

B. tomatoes

C. gardens

D. people

2. By saying"a win-win situation all around", Ms Gartin means that _____.

A. she is happier and her garden bigger

B. she may spend less and lose weight

C. she is selling more and buying less

D. she has grown more varieties of vegetables

3. Why is vegetable gardening becoming increasingly popular?

A. More Americans are doing it for fun.

B. The price of oil is lower than before.

C. There's growing need for fruits.

D. The cost of living is on the rise.

4. Which of the following might be the best title for the text?

A. Family Food Planning

B. Banking on Gardening

C. A Belt-tightening Move

D. Gardening as a Hobby

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政治变革对课程变革的制约表现在哪些方面。

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