Assess students' ability to apply lifecycle cost and carbon-footprint analysis to a daily high-school commute. Scope: compare common modes (walking, cycling, bus, carpool, single-occupant car, e-bike/scooter) using cradle-to-use emissions (vehicle manufacture, infrastructure, fuel/electricity, maintenance) and annualized costs (fuel/energy, maintenance, depreciation, fares). Require calculations per student per year for given distances, occupancy, and grid carbon intensity; analyze sensitivity, trade-offs, and justify a recommendation under stated constraints.