New PMP Question & Answers with explanation

Robert is a practicing project manager who is studying for his PMP® exam. During a study session with a colleague, he insists that it is important for project managers to consider all 49 project management processes, while his colleague insists that it is not necessary and that project managers should carry out only the necessary processes. Who is correct?
Select one
A project manager has been asked to calculate the payback period for her project. The project’s investment is $500,000, with expected cash inflow of $50,000 for the first two quarters and $100,000 for every quarter thereafter. What is the payback period?
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You are in the process of attaining and assigning resources to the project. You have both internal and external resources. You will be hiring your external resources using a work order against a contract you have with a local staffing agency. All of the following are true except for which one?
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The difference between project deliverables and project requirements is best described in which of the following options?
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A project sponsor asks the project manager to observe nonverbal feedback in the upcoming status meeting and adjust his presentation based on these observations. Which process is associated with these activities?
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