Businessman Tom Wolf talks to U.S. Rep. Allyson Schwartz before the Pennsylvania Democratic Gubernatorial Primary Debate last week in Philadelphia. Michael Perez/AP hide caption

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A Philadelphia Gas Works employee replaces old steel and cast-iron pipes with new plastic pipes that are less likely to leak. Jeff Brady/NPR hide caption

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The Ohmsett research facility, which researches oil spill response, was closed just before the Exxon Valdez accident. It was reopened as part of the measures included in the Oil Pollution Act of 1990. Jeff Brady/NPR hide caption

itoggle caption Jeff Brady/NPR

Washington Post advice columnist Judith Martin compares surveys to an insecure friend: " 'Are you sure you like me? Really? Do you like me?' And after a while you want to say, 'No! Go away!' " iStockphoto hide caption

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