A business case provides justification for undertaking a project, programme or portfolio. It evaluates the benefit, cost and risk of alternative options and provides a rationale for the preferred solution. A business case is essential for demonstrating the value of the project and securing the approval and funding from the governance. A business case is different from a scope statement, which defines the project boundaries and deliverables; a sponsor request, which initiates the project idea and seeks support; and a project charter, which authorizes the project and assigns the project manager. References = CompTIA Project+ PK0-005 Certification Study Guide, Chapter 3: Initiating Projects; What is business case? | APM

Explanation
Update the project charter. Updating the project charter would be the next step for the project manager after identifying the project team during the project initiation phase. A project charter is a document that formally authorizes a project and defines its purpose, scope, objectives, deliverables, milestones, roles and responsibilities, assumptions, constraints, risks, budget, and timeline. A project charter can help to align the expectations and interests of all stakeholders involved in a project and provide direction and guidance for planning and executing the project.

In order to find the client billing rate for a particular engineer, the project manager would need to refer to the SOW (Statement of Work). The SOW is a document that outlines the work to be performed, the timeframe for completion, and the cost of the project. It also includes information about the resources involved in the project and their billing rates. Reference: CompTIA Project+ Study Guide Section 2.2.
The project manager would need a statement of work (SOW) to find information about the client billing rate for a particular engineer. A SOW is a document that defines the scope of work for a project or contract. It usually includes information such as deliverables, milestones, timeline, costs, payment terms, quality standards, and acceptance criteria. A SOW can help to specify what services or products will be provided by whom, when, where, how, and for how much.

Explanation
The project manager can use the burn up chart to analyze the current status of the project based on its scope (value delivered), budget (cost), and schedule (time). A burn up chart is a graphical tool that shows how much work has been completed (burned up) versus how much work remains (scope) over time. It also shows how much budget has been spent (burned up) versus how much budget remains (budget) over time. A burn up chart can help to monitor and control the project progress and performance and identify any variances or deviations from the plan. The chart given shows that both scope and budget lines are above their respective target lines at any given time point. This means that less work has been completed than planned (scope variance) and more money has been spent than planned (budget variance) at any given time point. Therefore, the project is behind schedule and over budget.

A warranty period is the time during which a manufacturer or seller agrees to repair or replace a product that is defective or does not meet the specified standards. A warranty period can be expressed in terms of duration (e.g., one year) or usage (e.g., 10,000 miles). A warranty period is a form of consumer protection that obliges the manufacturer or seller to bear the costs of repairing or changing any part of the product that is not functioning properly1.