（）is a property of object-oriented software by which an abstract operation may be performed in different ways in different classes.

The strategies for handling risk comprise of two main types: negative risks, and positive risks. The goal ofthe plan is to minimize threats and maximize opportunities. When dealing with negative risks, there are three main response strategies（）,rransfer ,Mitigate.

The （）process ascertains which risks have the potential of affecting the project and documenting the risks＇ characteristics.

Developing the project schedule is often an iterative process. It determines the planned start and finish dates for project activities and milestones. Schedule development can require the review and revision of duration estimates and resource estimates to create an approved project schedule that can serve as a baseline to（）progress.

Estimating activity durations uses information on activity scope of（），required resource types, estimated resource quantities, and resource calendars.