题干

一束平行光线射到一个粗糙不平的物体表面上,下列说法中正确的是(  )

A:遵循光的反射定律,反射光线应该是平行的

B:遵循光的反射定律,反射光线向各个不同方向射出

C:只有相互平行的那部分光线遵循反射定律

D:这是漫反射现象,反射光线不遵循反射定律

上一题 下一题 0.0难度 选择题 更新时间:2013-06-03 05:33:48

答案(点此获取答案解析)

B

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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.