A risk register is used to document potential risks, including causes and impacts. This tool is essential for tracking and communicating project risks to stakeholders, as recommended by CompTIA Project+ for risk management.

The project manager should have considered environmental, social, and governance (ESG) factors during initial planning to prevent the situation of receiving a penalty for disposing of some computers improperly.
ESG factors are criteria that measure the sustainability and ethical impact of an organization's activities. They include aspects such as environmental protection, social responsibility, human rights, diversity, and corporate governance. Considering ESG factors can help to reduce risks, improve reputation, and enhance performance of an organization12

A gantt chart is a visual representation of a project timeline that shows the tasks, durations, dependencies, and resources of a project in a horizontal bar chart format. A gantt chart can help a project manager to calculate the progress of the whole project scope by comparing the planned and actual start and finish dates of each task, as well as the percentage of completion and the critical path. A gantt chart is also a useful tool for communicating the project status and performance to the sponsor and other stakeholders. Therefore, the first document that the project manager should update to calculate the progress of the whole project scope is the gantt chart. References = CompTIA Project+ Study Guide: Exam PK0-005, 3rd Edition, Chapter 6: Schedule Management1; CompTIA Project+ Certification Study Guide, 3rd Edition, Chapter 6: Schedule Management2; What Is a Gantt Chart? 7 Examples for Project Management3

A traceability matrix is a document that maps the requirements of a project to the deliverables, test cases, and changes that are produced to meet those requirements. It helps the project manager to track the origin, status, and impact of each requirement throughout the project life cycle. A traceability matrix can also identify who requested or approved each requirement. Therefore, the project manager can use the traceability matrix to identify who requested the specific item that caused the regression test to fail12.

This answer is based on the best practice of stakeholder management, which is to identify and document the communication preferences of each stakeholder or stakeholder group12. The project manager should update the stakeholder register with the information gathered from the stakeholder analysis, which includes the preferred communication channel for each stakeholder3. The preferred reported communication channel reflects the majority preference of the stakeholders, as well as the minority preference of the face-to-face communicators. The project manager should use this information to plan and execute effective communication throughout the project life cycle4. References = CompTIA Project+ Certification Study Guide5, CompTIA Project+ Certification Exam Objectives6, Stakeholder Register in Project Management1, What is a Stakeholder Register?2, How to Develop a Stakeholder Register3