Precedence Diagramming Method (PDM) is a method used in activity sequencing.There are four types of dependencies or precedence relationships in PDM.The initiation of the successor activity depends upon the completion of the predecessor activity is called（）

单项选择题Project selection methods involve measuring value or attractiveness to the project owner or sponsor and may include other organizational decision criteria（）is not a project selection method.

A.Benefit contribution
B.Expert judgment
C.Scoring models
D.Flowcharting

单项选择题假设某IT服务企业，其固定成本为30万元，每项服务的变动成本为1000元 次，提供每项服务的价格为1500元 次，那么该企业的盈亏平衡点为（）次。

A.200
B.300
C.600
D.900