Which system behavior are enabled when a create a project with multiple phase? NOTE: There are 2 correct answers to this question.

Which system behavior are enabled when a create a project with multiple phase? NOTE: There are 2 correct answers to this question.
A . Determination of the start-dates of subsequent phases
B . Rollup of activity cost allocations to phases
C . Rollup of resource requirements of tasks to phases
D . Determination of the start- and end-dates of tasks

Answer: A,D