题目

The task is very difficult. I wonder whether we will be able to finish it in the ________ of any other helpers. A . appearance B . escape C . spare D . absence 答案：D已知方程组，（1）若方程组的解满足x为正数，求m的取值范围；（2）若方程组的解满足x＞y，求m的取值范围．