相关习题
 0  76869  76877  76883  76887  76893  76895  76899  76905  76907  76913  76919  76923  76925  76929  76935  76937  76943  76947  76949  76953  76955  76959  76961  76963  76964  76965  76967  76968  76969  76971  76973  76977  76979  76983  76985  76989  76995  76997  77003  77007  77009  77013  77019  77025  77027  77033  77037  77039  77045  77049  77055  77063  109140 

科目: 来源: 题型:

【题目】若集合A={x,y|x2+y2≤16|,B={x,y|x2y-22≤a-1},且A∩B=B,则a的取值范围是

A.a≤1 B.a≥5 C.1≤a≤5 D.a≤5

查看答案和解析>>

科目: 来源: 题型:

【题目】下列词语中加线字的注音全都正确的一项是

A.袅nuó qiàn chù 蓊郁郁wěng

B. qiāo 妖童yuán

C.chàn chà zhà 不绝如

D.羞 xiè duó 斑驳

查看答案和解析>>

科目: 来源: 题型:

【题目】

Mathematics the language of science.

A.are

B. are going to be

C. is

D.is to be

查看答案和解析>>

科目: 来源: 题型:

【题目】

根据句意及首字母提示完成单词

The group of students from the USA will attend a I 【1】 about the Potala Palace in China next Sunday.

Early to bed and early to rise makes a man healthy and w 【2】

We Ieft early that morning. U 【3】 , we were caught in heavy rain and had to return halfway.

Now many families make use of refrigerators to keep the r 【4】 of meals as well as fresh food.

People often get tired of too many c 【5】 while watching TV series.

查看答案和解析>>

科目: 来源: 题型:

【题目】

It looked as if hard times didn't have any effect on her, for she

so charming and beautiful.

A. remained

B. was remained

C. was remaining

D. had been remained

查看答案和解析>>

科目: 来源: 题型:

【题目】请补充完整文段结尾的那句话,使其能够概括全段的内容,并且语意连贯,表达简洁,能够体现文段前后的内在联系。20字左右。

作为20世纪最伟大的物理学家之一,爱因斯坦对物质世界的思考和认识是深入的。他的狭义相对论成功地揭示了能量与质量之间的关系,解决了长期存在的恒星能源来源的难题。其广义相对论也解决了一个天文学上多年的不解之谜——水星近日点的进动,并推断出后来被验证了的光线弯曲现象。但就是这位蜚声全球的科学家,在20世纪30年代收到以色列当局诚挚邀请他担任以色列总统的信时,断然拒绝了邀请。能够成为犹太国的总统,无疑是爱因斯坦人生的又一项辉煌成就。但出乎人们意料的是,爱因斯坦毫不犹豫地拒绝了。他说:我整个一生都在同客观物质打交道,既缺乏天生的才智,也缺乏经验来处理行政事务以及公正地对待别人。所以,本人不适合担当如此高官重任。可以说,爱因斯坦是位。

查看答案和解析>>

科目: 来源: 题型:

【题目】

根据短文内容,从短文后的七个选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Urbanization

Until relatively recently, the vast majority of human beings lived and died without ever seeing a city. The first city was probably founded no more than 5,500 years ago. 【1】. In fact, nearly everyone lived on farms or in tiny rural (乡村的) villages. It was not until the 20th century that Great Britain became the first urban society in history--- a society in which the majority of people live in cities and do not farm for a living.

Britain was only the beginning. 【2】 .The process of urbanization ——the migration (迁移) of people from the countryside to the city--- was the result of modernization, which has rapidly transformed how people live and where they live.

In 1990, fewer than 40% of Americans lived in urban areas. Today, over 82% of Americans live in cities. Only about 2% live on farms. 【3】 .

Large cities were impossible until agriculture became industrialized. Even in advanced agricultural societies. It took about ninety-five people on farms to feed five people in cities. 【4】 . Until modern times, those living in cities were mainly the ruling elite(精英) and the servants, laborers and professionals who served them. Cities survived by taxing farmers and were limited in size by the amount of surplus food that the rural population produced and by the ability to move this surplus from farm to city.

Over the past two centuries, the Industrial Revolution has broken this balance between the city and the country. 【5】 . Today, instead of needing ninety-five farmers to feed five city people, one American farmer is able to feed more than a hundred non-farmers.

A. That kept cities very small.

B. The rest live in small towns.

C. The effects of urban living on people should be considered.

D. Soon many other industrial nations become urban societies.

E. But even 200 years ago, only a few people could live in cities.

F. Modernization drew people to the cities and made farmers more productive.

G. Modern cities have destroyed social relations and the health of human beings.

查看答案和解析>>

科目: 来源: 题型:

【题目】选出下列加横线的字的注音无误的一组

A.喝(yāo) (shuì) (yáo) 透(qìn)

B.问(kǎo) (gǔn) 养(sì) (yín)

C.木(zhà) 堂(lòng) (lǒu) 水门(dīng)

D.油(kāi) 待(nüè) (duò) 生杀夺(yú)

查看答案和解析>>

科目: 来源: 题型:

【题目】某厂生产的零件尺寸服从正态分布N(25,0.032),为使该厂生产的产品有95%以上的合格率,则该厂生产的零件尺寸允许值范围为________.

查看答案和解析>>

科目: 来源: 题型:

【题目】过点2,1的直线中,被圆x2+y2-2x+4y=0截得的弦最长的直线的方程是

A.3x-y-5=0 B.3x+y-7=0

C.3x-y-1=0 D.3x+y-5=0

查看答案和解析>>

同步练习册答案