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Water: no cholesterol, fat free, zero sugar -- Infrastructure: pipes, wires, roads, bridges, railroads, dams, airports, and levees -- Floods: when the levees break -- Garbage: trash talk -- Soil, crops, and food: dirt and nutrition -- Fossil fuels: energy from the past -- Alternative energy sources: energy for the future -- The nuclear energy controversy: radiation for everyone -- Climate change: what have we done? -- Air pollution: lung disease -- Conclusion: is there hope?
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