实验表明，过滤器可以生产更安全的饮用水。

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Jeffrey Schwarz
Pennsylvania
Jeff Schwarz
AmeriCorps
Tests have shown that the filter produces safe drinking water. On a good day, Jeffrey Schwarz says the studio in the library can produce 20 filters. To make one, clay is mixed with a material that burns. It could be sawdust or agricultural waste like grain hulls, cocoa or coffee shells. Pine ne…
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