Below is an activity on node or precedence diagram for a project starting with activity $$A$$ and ending with activity $$S$.$ Each activity has an estimated time duration and the arrows indicate what activities are dependent on others and which can be done simultaneously. What is the project completion time $($overall duration$)?$

Identify the project$$s critical path? What does it mean?

Which activity has the greatest slack time $($most amount of flexibility with allocation of resources and start time$)$ and what is that slack time?

Provide $2$ suggestions for compressing the project timeline, if needed.