题目

 Children in the countryside can receive education ________ free since last year. A. for                B. in               C. of            D. on 答案：A设函数f(x)＝ln(1＋x)＋mln(1－x)是偶函数，则( )A.m＝1，且f(x)在(0,1)上是增函数B.m＝1，且f(x)在(0,1)上是减函数C.m＝－1，且f(x)在(0,1)上是增函数D.m＝－1，且f(x)在(0,1)上是减函数