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设有员工实体Employee(员工号,姓名,性别,年龄,电话,家庭住址,家庭成员,关系,联系电话)。其中,“家庭住址”包括邮编、省、市、街道信息;“家庭成员,关系,联系电话”分别记录了员工亲属的姓名、与员工的关系以及联系电话,且一个员工允许有多个家庭成员。 员工实体EmPloyee的主键为 (40) ;该关系属于 (41) ;为使数据库模式设计更合理,对于员工关系模式Employee (42) 。

A. 只允许记录一个亲属的姓名、与员工的关系以及联系电话
B. 可以不作任何处理,因为该关系模式达到了3NF
C. 增加多个家庭成员、关系及联系电话字段
D. 应该将家庭成员、关系及联系电话加上员工号作为一个独立的模式

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Stephen M. Saland, chairman of the State Senate Education Committee, is a conservative upstate Republican, and Steven Sanders, chairman of the Assembly Education Committee, is a liberal New York City Democrat. But when it comes to education, they have much in common. Neither is a fan of the federal No Child Left Behind Law and its extensive testing mandates. Both say that standardized tests are too dominant in public schools today.That has at times put the two education chairmen in conflict with the state education commissioner, Richard P. Mills. (46) During his 10-year tenure, Dr. Mills has turned New York into one of the most test-driven public systems in the nation, requiring students to pass five state tests to graduate.(47) For months now, the legislative leaders and the commissioner have been locked in a little-noticed fight over the future of 28 small alternative public high schools, a fight that may well be the final stand for opponents of standardized testing in New York.Senator Saland and Assemblyman Sanders are doing their best to protect these schools in New York City (Urban Academy, Manhattan International), Ithaca (Lehman Alternative) and Rochester (School Without Walls) and help them retain their distinctive educational approach. (48) Instead of the standard survey courses in global studies, American history, biology and chemistry pegged to state tests, these schools favor courses that go into more depth on narrower topics. At Urban Academy, there are courses in Middle East conflicts, world religions, post-Civil War Reconstruction and microbiology.In the mid-1990’s, the former education commissioner, Thomas Sobol, granted these 28 consortium schools (serving 16,000 students, about 1 percent of New York’s high school population) an exemption from most state tests. That permitted a more innovative curriculum, and students were evaluated via a portfolio system that relies on research papers and science projects reviewed by outside experts like David S. Thaler, a Rockefeller University microbiology professor, and Eric Foner, a Columbia history professor.The Gates Foundation, which has given hundreds of millions of dollars to start small high schools nationwide, is so impressed with these schools, and it regularly sends educators to New York to see how they’re run.But the testing exemption for these schools is about to expire, and Commissioner Mills does not want it renewed. He believes that all students, without exception, should take every test.Recently, Senator Saland defied the commissioner. He shepherded a bill through the Republican-controlled Senate that passed 50 to 10 and would continue these schools’ waivers for four years. (49) Senator Saland’s bill does require that students pass the state English and math tests to graduate, letting the state gauge the alternative schools’ performance versus mainstream schools.On the Senate floor, Senator Saland noted that while 61 percent of consortium students qualified for free lunches and three-quarters were black or Hispanic, 88 percent went on to college, compared with 70 percent at mainstream schools that give state tests. (50) He said that the dropout rate was half the rate at mainstream schools and that on the one statewide test these students took regularly, English, they scored an average of 77, outdoing mainstream students by 5 points. Instead of the standard survey courses in global studies, American history, biology and chemistry pegged to state tests, these schools favor courses that go into more depth on narrower topics.

水稻是______日照植物。

凡是与群落发育有关的直接或间接的生态因子,都可成为演替的______。

绿色植物并没有被吃尽的主要原因是植物在进化过程中发展了防卫机制。( )

A. 对
B. 错

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