The lead auditor is responsible for determining the scope of the audit. This involves defining the boundaries of the audit, including which processes, departments, and activities will be examined. The lead auditor ensures that the audit objectives are clear and that the audit plan effectively covers the necessary areas to assess compliance and performance against specified standards and requirements.

Earned Value Management (EVM) includes several key metrics, one of which is the budgeted cost of work performed (BCWP). Here’s a detailed explanation:

Earned Value (EV) : Represents the value of work actually performed in terms of the budget assigned for that work.

Planned Value (PV) : The budgeted cost for the work planned/scheduled.

Actual Cost (AC) : The actual cost incurred for the work performed.

Performance Measurement : BCWP is crucial for comparing planned work with actual progress and costs, helping in performance measurement and project forecasting.

References :

"Project Management: A Systems Approach to Planning, Scheduling, and Controlling" by Harold Kerzner.

PMI’s "A Guide to the Project Management Body of Knowledge (PMBOK Guide)".

Internal failure costs are costs associated with defects found before the product reaches the customer. These costs include: Investigation of defects: Identifying and analyzing defects within the development process. Rework: Fixing defects found during internal testing or audits. Scrap: Discarding defective parts or products. Downtime: Halting production or development to address defects. Among the given options, investigating the cause of build defects is an internal failure cost because it pertains to finding and analyzing issues within the software before it is released to customers. Reference: "Quality Planning and Analysis" by J.M. Juran and F.M. Gryna "Total Quality Management" by Bester field et al. 

For a risk management plan to be effective, it should be updated regularly to address new risks. Here’s why:
Dynamic Nature of Projects : Projects are dynamic and subject to changes that can introduce new risks.
Proactive Risk Management : Regular updates ensure that the risk management plan remains relevant and effective in identifying and mitigating current risks.
Continuous Monitoring : Enables continuous monitoring and reassessment of risks, ensuring timely responses to emerging threats.
Stakeholder Confidence : Regular updates demonstrate a proactive approach to risk management, building stakeholder confidence in the project’s management.
References :
"Project Risk Management: A Practical Implementation Approach" by Michael M. Bissonette.
"The Risk Management Handbook: A Practical Guide to Managing the Multiple Dimensions of Risk" by David Hillson.