简述正线RM车辆段RM的相同点和不同点。
参考答案：
相同点：都是限速25KM/H
不同点：车辆段RM可以退行，而正线RM不能退行。
—What do you think has caused his heart attack?
—It is ______.
A．because of his overweight
B．due to his being overweight
C．his being overweight
D．he is so overweight
估算活动资源过程的输出包括（）。
A.资源价格
B.活动持续时间估算
C.资源分解结构
D.出版的估算数据
