] In the following activity diagram, there is an expansion region which includes two action steps in sequence: Write Proposal, and Review Proposal. Let's assume that a student team need to spend 2 hours to "Write Proposal", and the course instructor needs 2 hours to review a proposal. We also assume there are 10 teams in the class (i.e., there are 10 proposals to write and review). (4) Which mode do you think makes sense for this activity? Explain why