20世纪初,打开了原子能时代大门的伟大科学家是牛顿。

题型:判断题

问题:

20世纪初,打开了原子能时代大门的伟大科学家是牛顿。

考点:启蒙运动(伏尔泰,卢梭,孟德斯鸠)自由主义文艺复兴哥白尼“太阳中心说”
题型:判断题
已知中心在原点,焦点在坐标轴上的椭圆Ω,它的离心率为
1
2
,一个焦点和抛物线y2=-4x的焦点重合,过直线l:x=4上一点M引椭圆Ω的两条切线,切点分别是A,B.
(Ⅰ)求椭圆Ω的方程;
(Ⅱ)若在椭圆
x2
a2
+
y2
b2
=1(a>b>0)
上的点(x0,y0)处的椭圆的切线方程是
x0x
a2
+
y0y
b2
=1
.求证:直线AB恒过定点C;并出求定点C的坐标.
(Ⅲ)是否存在实数λ,使得|AC|+|BC|=λ|AC|•|BC|恒成立?(点C为直线AB恒过的定点)若存在,求出λ的值;若不存在,请说明理由.
题型:判断题
x2y
z
(x<0,y>0,z>0)化简的结果是(  )
A.x
y
z
B.
x
z
yz
C.-
x
z
yz
D.-x
y
z
题型:判断题

Passage Two

During the last thirty years, the international economy has experienced a basic change. Improvements in the Internet and other communications have had important effects on world markets. Faster methods of transport from one place to another have made the world seem smaller to the businessmen. As a result, the world no longer. consists of a number of separate economies under the control of different nations. Instead, the nations have been integrated into a single economy, and the integration is becoming more and more complete every year. For the first time in history, we can truly speak of a global economy.
The most dramatic example of this integration was the oil crisis of 1973 and 1974. It came as a great surprise to the public in the industrial nations to discover that they depended so heavily on imported oil. However, the best evidence for the growing integration is the rapid expansion in the volume of world trade. It went up by about 7% a year during the decade from 1990 to 2000, and in several quasi-industrial (半工业的) countries the growth was even more rapid. As a result, some imported products have become as common as domestic commodity. Some of them are too common for the public to any more realize they are foreign.
Production has also become international, which is manifested by the large corporations stepping across national borders and established branches and subsidiaries in several different countries. As an example, U.S. companies are building automobiles in Canada, Germany, Britain and Japan. In some cases, components of an automobile are produced abroad and shipped to the United States, where it is then finished with the imported parts. When even the United States has the largest number of such corporations, it is not the only. Other multinationals, for instance, are based in Japan, France, Germany, the UK and Italy.
Labor, too, is much more mobile than in the past. Both skilled and unskilled workers can now readily migrate from one country to another. In Europe, for example, there are large numbers of Turkish workers employed in the Germany Economy. Doctors, lawyers, and other professionals are also finding it easier to work in foreign countries. The labor market has become international, and the number of expatriate workers is continuing to grow.

People in industrial nations felt greatly surprised by the oil crisis in 1973 and 1974 because ______ .

A.they didn’t expect the crisis to occur so soon

B.they couldn’t live without oil

C.they found they were so dependent on foreign countries

D.they realized they were not the per nations at all

题型:判断题

某病人血涂片,经瑞氏染色后,观察时发现血涂片异常蓝染,且布满颗粒。

异常蓝染的原因最可能的是

A.用新推片制备血涂片
B.缓冲液偏碱
C.染料配制时间过长
D.用已处理过的新玻片制备血涂片
E.用自来水冲洗

题型:判断题

催化剂过滤器后己水中含催化剂的处理方法为()。

A、减少催化剂加料量

B、将过滤器切出检修

C、将并联的两个过滤器改串联运行

D、将预涂不充分的过滤器重新预涂

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