改变禅让的传统，第一个实现王位世袭制的是（    ）

（Ⅰ）求角C的值；

（Ⅱ）若c=2，且△ABC为锐角三角形，求a+b的取值范围．

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       Changqing has a long history but it is the new district of Jinan. It ____  in the west of Jinan. and covers 1178 square kilometers. The ____  of Changqing is about 530,000. It has convenient transportation ____  it's easy to get here. There are many ancient places of interest for you to visit, such as Lingyan Temple, Xiaotang Hill and so on. It has changed a lot since it became the new district of Jinan. Now it has 15 colleges or universities. You can make your ____ come true there. And the Expo garden which was built newly attracts thousands____ visitors every year. Welcome to Changqing, and you will enjoy yourself.