-1/7,1/7,1/8,-1/4,-1/9,1/3,1/10,() A. -2/5;B. 2 -1/7,1/7,1/8,-1/4,-1/9,1/3,1/10,()A.-2/5;B.2/5;C.1/12;D.5/8; 参考答案 查看答案