I need help understanding dependency graphs

There are 14 tasks and below table shows the task dependency with required time to complete the task. Table 1. Dependency among Tasks 4. Draw a task-dependency graph. (5 points) 5. What are the critical path length and average degree of concurrency? ( 5 points) 6. Show an efficient mapping of the task-dependency graph of the decomposition shown in Table 1 on to three processes. (10 points) 7. Describe and draw an efficient mapping of the task-dependency graph of the decomposition shown in Table 1 onto four processes. ( 10 points) 8. As shown in Table 1, each task takes a unit amount of time. Compare the performance of question 6(3 processes) and 8 ( 4 processes) in terms of maximum concurrency, computation time, process idling time, and communication. (10 points)