已知某样品中存在甲、乙、丙、丁、戊五种蛋白质分子，其分子大小、所带电荷的性质和数量情况如图所示，下列有关该样品中蛋白质的分离的叙述正确的是(　　)

（Ⅰ）给出a的一个取值，使得曲线y=f（x）存在斜率为0的切线，并说明理由；

（Ⅱ）若f（x）存在极小值和极大值，证明：f（x）的极小值大于极大值．

12年9月10日，日本政府不顾中方一再严正交涉，宣布“购买”钓鱼岛及其附属的南小岛和北小岛，实施所谓“国有化”。中国政府和人民对此表示坚决反对和强烈抗议。不少中学生也十分关注钓鱼岛事件。请回答题目。 

阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。

    One day, Daisy dreamed a strange dream. She flew in a wonderful carpet to talk with an antelope in Tibet. The antelope told her they were hunted because of their fur which can be used to make sweaters like hers.

Later, she flew to Zimbabwe where she talked with an elephant and got to know the farmers there no longer hunted them. That's because the government decided to help and the farmers finally made a lot of money.

    At last, she arrived at the thick rainforest where a monkey told her “no rain forest, no animals and no drugs.” Although finally everything was gone, she had learned so much.