Answer three parts using the STAR method and concrete metrics: (1) Most challenging project: what was the goal, constraints, and your specific ownership; how did you de-risk, prioritize, and measure success; cite quantitative impact and a hard trade-off you made. (2) Convince others: describe a time you persuaded a skeptical stakeholder or senior engineer—what objections they had, how you adapted communication, what data/prototype you used, a concession you accepted, and how you handled being wrong. (3) Help others: describe how you unblocked or mentored a teammate—what you taught, how you ensured long-term autonomy, how you measured the outcome (e.g., cycle time, incidents), and how you created a psychologically safe environment. Include a brief retrospective for each on what you’d do differently next time.