Final answer:
In MS Project, durations of phases containing subordinate tasks can be changed manually by the user or specified by the software.
Step-by-step explanation:
In MS Project, durations of phases containing one or more subordinate tasks can be changed manually by the user. This allows the user to modify the duration of a phase based on their understanding of the project and its tasks. For example, if the user realizes that a specific phase will take longer than originally estimated, they can increase the duration to reflect that.
On the other hand, durations of phases can also be specified only by MS Project. This means that the software automatically calculates the duration of a phase based on the estimated duration of its subordinate tasks.
The durations of phases in MS Project can be changed manually by the user or specified by the software.