To solve this problem using the priority list method with two processors, we need to follow these steps:

1. Assign Tasks to Processors Based on Priority:

   • We use the priority list: T6, T5, T1, T7, T4, T3, T2.
   • Assign the tasks to the processors according to their availability and the task durations.

2. Calculate the Starting Times for Each Task:

   • We must ensure that tasks are scheduled as early as possible, respecting the task dependencies (as indicated by the graph).

Step-by-Step Scheduling

1. T6 (7 units):

   • This is the highest-priority task, so it is assigned to Processor 1 at time 0.

2. T5 (8 units):

   • Assigned to Processor 2 at time 0.

3. T1 (2 units):

   • This task should ideally be assigned to a processor as soon as one becomes available.
   • Processor 1 finishes T6 at time 7, so T1 can start at time 7.

4. T7 (10 units):

   • This should start as soon as a processor is free.
   • Processor 2 will finish T5 at time 8, so T7 can start at time 8.

5. T4 (4 units):

   • Processor 1 finishes T1 at time 9, so T4 can start at time 9.

6. T3 (6 units):

   • Processor 1 finishes T4 at time 13, so T3 can start at time 13.

7. T2 (12 units):

   • Processor 2 finishes T7 at time 18, so T2 can start at time 18.

Summary of Scheduling

• Processor 1:

  • T6: Start at 0, End at 7
  • T1: Start at 7, End at 9
  • T4: Start at 9, End at 13
  • T3: Start at 13, End at 19

• Processor 2:

  • T5: Start at 0, End at 8
  • T7: Start at 8, End at 18
  • T2: Start at 18, End at 30

Answers to the Specific Questions:

• Task 4 is done by: Processor 1, starting at time 9.
• Task 6 is done by: Processor 1, starting at time 0.

Would you like more details on how this was calculated, or do you have any further questions?

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Here are 8 related questions to expand your understanding:

1. What are some other methods for task scheduling in a multi-processor system?
2. How do task dependencies influence the scheduling order?
3. What is a critical path, and how does it relate to task scheduling?
4. How can scheduling algorithms be optimized for minimizing completion time?
5. What happens if a task with a lower priority has a dependency on a higher-priority task?
6. How does the introduction of more processors affect the scheduling strategy?
7. What are the potential drawbacks of the priority list method?
8. Can this method be applied to dynamic task scheduling where tasks are added during execution?

Tip: When scheduling tasks, always verify that the task dependencies are respected; this ensures that the final output will be logically consistent.