New PMP Question & Answers with explanation

Robert’s project is a high-priority project for his organization. Project stakeholder engagement is crucial for the project’s success. Robert needs to discuss the project stakeholder engagement levels with his project team on a regular basis. Which of the following is the best platform where Robert can review this with his team?
Select one
Which of the following statements regarding team-building is correct?
Select one
The Work Breakdown Structure (WBS) is a deliverable-oriented hierarchical decomposition of the work the project team will execute to accomplish the project objectives and create required deliverables. The Create WBS process falls under which knowledge area?
Select one
A project was estimated to cost $100,000 with a timeline of five months. Due to some unusual causes, the schedule was delayed. At the end of the third month, the project manager reviews the project and finds that the project is 40 percent complete and Actual Costs are $60,000. Assuming that the cost variations observed to date would not continue going forward, the Estimate to Complete (ETC) for the project are:
Select one
You are authorized to approve expenditures above $15,000. For the last several weeks, you have been negotiating the terms and pricing of a contract with a vendor, and you want to keep costs as low as possible. This has been an exceedingly difficult negotiation process. A colleague suggests you tell the vendor you can only approve expenses below $10,000 as a way to keep the price low. What do you do?
Select one