铁板甲形状是等腰三角形,其顶角为45°,腰长为20cm,铁板乙的形状是直角梯形,

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问题:

铁板甲形状是等腰三角形,其顶角为45°,腰长为20cm,铁板乙的形状是直角梯形,两底分别为7cm,16cm,且有一个角为60°,现在我们把这两块铁板任意翻转,分别试图从一个直径为14cm的圆洞中穿过,若不考虑铁板厚度,则结果是(  )

A.甲能穿过,乙不能穿过

B.甲不能穿过,乙能穿过

C.甲、乙都能穿过

D.甲、乙都不能穿过

考点:三角形的内心、外心、中心、重心
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观察思考下面的解题过程和结果,是否正确?

一个高3分米,底面直径为20厘米的圆柱形水桶里装满水,水中放着一个底面直径为18厘米,高为15厘米的铁质圆锥体,当这个铁质圆锥体取出后,会发生怎样的变化?结果如何?

当这个铁质圆锥体取出后,桶内水面要降低,因为这个物体原来占据了一些空间,结果怎样,就要先求圆锥体的体积,再求变化的结果.

(1)圆锥的底面积

(2)圆柱的底面积

(3)圆锥的体积

(4)水面降低的米数

1271.7÷314=4.05(厘米)

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设关系R和关系S具有相同的属性个数,且相应的属性取自同一个域则{t|t∈R∧┑t∈S}t是元组变量其中结果关系是:()

A.R∪S 

B.R-S 

C.R∩S 

D.R-(R-S)

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C++语言提供的基本控制结构可以分为3种类型:顺序结构、 【9】 和循环结构。

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完形填空。

     There are some special traditions in Hawaii. People are very friendly and always welcome

visitors. They give visitors a lei, a long necklace of beautiful fresh flowers. Men wear bright

flowered shirt and women often wear long flowered dresses. There are traditional Chinese,

Japanese and Filipino holidays and all the holidays from the United States. They call Hawaii

the Aloha State. Aloha means both hello and goodbye. It also means " I love you".

     Usually when people from different countries, races and traditions live together, there are

serious problems. There are so many people  living in  Hawaii, but in general, people have

learned to live together in peace.

     Hawaiians get most of their money from visitors, and most of the visitors come from the

mainland and from Japan. There are so many people living in Hawaii now that there are

residential areas ( 住宅区 ) where there used to be farms. Some of the big sugar and pineapple

companies have moved to the Philippines, where they do not have to pay workers as much

money. The families of the first people who came from the U.S mainland own the important

banks and companies .Japanese are also buying or starting business here.

1. The author wants to show that _____.

A. we should all go to Hawaii.

B. it is possible to learn to live together in peace.

C. it is not possible to live together in peace.

D. Hawaii is the only place where there is peace.

2.  A  lei is _____. 

A. group of flowers                      

B. bright flowered shirt  

C. way to say hello and goodbye            

D. necklace of flowers

3. _____ plays an important part in the development of Hawaii. 

A .Modern industry  

B. Agriculture  

C. The air line  

D. Tourist trade

4. A good title for this article might be_____. 

A. Hawaii, the Aloha State            

B. Living in Peace Together

C. The Flowers of Hawaii              

D. The Problems of Hawaii    

题型:选择题

ZIGBEE是哪个协议的代名词()

A.IEEE802.15.1

B.IEEE802.15.4

C.IEEE802.11.1

D.IEEE802.11.4

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