题干

宁夏的硒砂瓜现今已享誉区内外,西瓜富含硒元素,有延年益寿、抗衰老、抗癌作用,因之得名“硒砂瓜”。二氧化硒(Se)是一种氧化剂,其被还原后的单质硒可能成为环境污染物,通过与浓HNO3或浓H2SO4反应生成SeO2以回收Se。在回收过程当中涉及到如下两个化学反应①SeO2+4KI+4HNO3Se+2I2+4KNO3+2H2O;
②Se+2H2SO4(浓)2SO2↑+SeO2+2H2O
下列有关叙述正确的是

A:SeO2、H2SO4(浓)、I2的氧化性由强到弱的顺序是H2SO4(浓)> SeO2> I2

B:①中Se是氧化产物,I2是还原产物

C:反应①中KI是氧化剂,SeO2是还原剂

D:反应①中每有0.6 mol I2生成,转移电子数目为2.4NA

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      May the first is an important date in the college admission process in the United States. This is the last day for high school seniors to accept or reject offers of admission in the fall. But according to a recent report, there is a great change. Acceptance rates at the top colleges this year were lower than ever. ____ 

      These days, college applicants are applying to more colleges because online and common applications make the process easier. ____ On the other hand, deciding students for top colleges to accept can be difficult because it takes much time. Students may not like being put on waiting lists.Also, common colleges work more to getthe students they accept to accept them. Some colleges hold visiting days that offer a chance to attend classes and stay overnight. Some universities send gifts. ____

      For many families, the most important thing colleges can do is show them the money, especially this year; the weak economymakes parents nervous. ____ The recent problems that spread from thehousing market to credit markets have even affected student's loans.Solately, top schools have to spare lots of money to increase their financial aidfor students.

____The Education Department expects the number of highschool graduates to start to go down. This will happen as the last of thechildren of the baby boom generation finish high school. Thenumber is not expected to start rising again until 2016.

A.Besides, top colleges are facing changesin the population.

B.What contributes to it?

C.But a mistake can be costly if ithappens.

D.But top colleges ignore them..

E.They have international students whoknow English.

F.It can mean several acceptances tochoose from.

G.They cannot afford college as planned.