问题描述：
老师这几道题帮忙看一下 谢谢啦
http://zhidao.baidu.com/question/495393504679205404.html?quesup2&oldq=1
http://zhidao.baidu.com/question/1881952657690247788.html?quesup2&oldq=1
http://zhidao.baidu.com/question/918108885266586299.html?quesup2&oldq=1
http://zhidao.baidu.com/question/495393504679205404.html?quesup2&oldq=1
http://zhidao.baidu.com/question/1881952657690247788.html?quesup2&oldq=1
http://zhidao.baidu.com/question/918108885266586299.html?quesup2&oldq=1
问题解答：
我来补答展开全文阅读