题干

2007年我国铁路再次实施大提速,提速后运行速度可达250km/h。铁路提速要解决很多技术上的问题,其中弯道改造就是一项技术含量很高的工程。在某弯道改造中下列论述正确的是(   )

A:保持内外轨高度差不变,适当增加弯道半径

B:减少内外轨高度差,保持弯道半径不变

C:减小内外轨高度差,同时适当减小弯道半径

D:只要减小弯道半径,内外轨高度差保持不变或减小都行

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A

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    People in the western state of California who are in the United States illegally can now request a driver's license. The law went into effect on January l. California is not the first American state with such a law, but it has the largest number of illegal immigrants. More than a million people began to request licenses shortly after the new state law went into effect. Among them was Christian Alvarado. Mr. Alvarado entered the United States from El Salvador eight years ago without permission from the U.S. government. Some call such people "illegal immigrants." Others call them "undocumented immigrants".

    Mr. Alvarado thinks it so exciting, for he has been waiting for the license for a long time. But some are worried that their personal information will be used to find them and deport them. Armando Botello is a spokesman for the California Department of Motor Vehicles, or DMV. He says people should not be afraid, for such information will not be shared.

    The new licenses are the same as licenses given to citizens except that they have the words "Federal Limits Apply". That means the license cannot be used to travel on an airplane or enter a federal building. Ana Garcia, working at the Central American Resource Center, says some illegal immigrants fear those words will be used to abuse them. Civil rights groups say the police and others will not.

    Dan Schnur, a political scientist at the University of Southern California, said that the main argument against the new law is that it rewards illegal behavior. But Professor Schnur argued that young, white Americans generally support immigration reform, including giving driver's licenses to illegal immigrants

    "It's simply because they grew up in a much more multicultural society than their parents or their grandparents did." Professor Schnur says he believes the changes in beliefs about illegal immigrants that have taken place in California will spread throughout the United States.