Assess and compare lifecycle costs and greenhouse‑gas emissions of gasoline and electric commuter cars to recommend the best option for a high‑school carpool program. Students will calculate total cost of ownership (purchase, fuel/charging, maintenance, insurance, depreciation, battery replacement) and lifecycle emissions (manufacturing, operational, end‑of‑life) using provided vehicle specs, local electricity grid carbon intensity, typical commute distances, and carpool occupancy; deliver a justified recommendation with key assumptions and a brief sensitivity analysis.