不属于工作时间估计的依据是( )。
A．工作清单
B．约束条件
C．项目范围说明书
D．历史资料
参考答案：C
There used to be a tall tree in front of our classroom, ____? [ ]
A. used there
B. didn't there
C. wasn't there
分馏塔停工后要进行哪些处理？
