要求查询数学成绩大于80并且平均成绩大于85的学生,请各位大佬看看 表结构如下: name,subject,score ('张三','语文',90), ('张三','数学',82), ('张三','英语',60), ('李四','语文',88), ('李四','数学',85), ('李四','英语',72), ('王五','语文',91), ('王五','数学',98), ('王五','英语',96), ('牛冲','语文',87), ('牛冲','数学',77), ('牛冲','英语',59)