在等差数列{an}中,d=1,S98=137,则a2+a4+a6+…+a98等于

题型:选择题

问题:

在等差数列{an}中,d=1,S98=137,则a2+a4+a6+…+a98等于

A.91

B.92

C.93

D.94

考点:等差数列的定义及性质
题型:选择题

患者,女性,30岁,双眼上睑下垂渐加重1年,休息、睡眠后症状可改善。

(如图),最可能是以下哪种疾病()

A.上睑肿块

B.先天性上睑下垂

C.重症肌无力

D.动眼神经不全麻痹

E.沙眼

题型:选择题

汽车使用无铅汽油后,仍会对大气造成污染。

题型:选择题

阅读理解。

      Man is a land animal, but he is also closely tied to the sea. Throughout history the sea has served

the needs of man. The sea has provided man with food and a convenient way to travel to many parts

of the world. Today, nearly two-thirds of the world's population live within 80 kilometers of the sea

coast.

      In the modern technological world, the sea offers many resources to help mankind survive.

Resources on land are beginning to be used up. The sea, however, still can be hoped to supply many

of man's needs.

     The list of riches of the sea yet to be developed by man's technology is impressive. Oil and gas

explorations have been carried out for nearly 30 years. Valuable amounts of minerals exist on the

ocean floor ready to be mined.

     Fish farming promises to be a good way to produce large quantities of food. The culture of fish

and shellfish is an ancient skill practiced in the past mainly by Oriental people.

     Besides oil and gas, the sea may offer new sources of energy. Experts believe that the warm

temperature of the ocean can be used in a way similar to the steam in a steamship. Ocean currents

and waves offer possible use as a source of energy.

     Technology is enabling man to explore ever more deeply under the sea. The development of

strong, new materials has made this possible.

     The technology to harvest the sea continues to improve. Experts believe that by the year 2050

the problems that prevent us from exploiting fully the food, minerals, and energy sources of the sea

will be largely solved.

1. What is the beat title for the passage?

A. Needs of Man.              

B. Sea Harvest and Food

C. Sea and Sources of Energy    

D. Sea Exploring Technology.

2. It can be inferred from the passage that ______.

A. man hasn't completely made use of the riches of the sea

B. technology for exploring the sea has been solved

C. harvesting rice in the sea will be made possible

D. in the near future man can live on the ocean floor

3. Why does the author mention a steamship in paragraph 5?

A. To illustrate that man can make use of sources of energy from the sea.

B. To show that a steamship is better than other kinds of ships.

C. To argue that man should use steamships.

D. To indicate that it is warmer in the ocean than on land.

4. According to the author, technology is important because ______.

A. resources on land are running short in ten years

B. man can use it to explore the deeper sea

C. it is a lot of fun diving into the sea

D. ancient people used it to explore the sea

5. According to the author, when will the problems to explore the deeper sea largely be solved?

A. In the next generation.              

B. At the end of the 20th century.

C. In the near future.                  

D. By the middle of the 21st century.

题型:选择题

对于存在液化土层的地基,应根据液化指数综合划分地基的液化等级,下述不正确的是()。

A.测试点标准贯入锤击数的实测值大于该点临界值时,液化指数为0 

B.对液化土层标贯锤击数实测值越小,液化指数越大 

C.当标贯锤击数实测值与临界值一定时,测试点深的液化指数相对较大 

D.当液化指数为10时,对判别深度为15m的场地液化等级为中等

题型:选择题

在行使代位求偿权时,若保险人追偿到的款额大于其赔偿给被保险人的款额,应对超过的部分采取( )的分配方式。

A.据为已有

B.归还被保险人

C.与被保险人平分

D.上缴有关部门

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