Grocery Shopping

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Reduce Your Impact on the Environment gives you easy ways to reduce your impact on the global environment. (Unplug your cell phone charger once the phone has been charged! Buy apples from Washington or New York, not Fiji!) You can compare your carbon footprint to others' (by city or country), and hook up with like-minded people in your area (if you want to carpool or sponsor a farmers' market).

So take the O challenge and reduce your footprint by 10 percent. If 3 million readers succeed, we'll accomplish the environmental equivalent of planting and caring for 91 million tree seedlings for 10 years, or removing 690,000 cars from the road, or reducing the emissions of Liechtenstein 13 times over.