<http://webisa.webdatacommons.org/219487282>	<http://www.w3.org/ns/prov#value>	"coal can mostly be ???ltered out of air" .
<http://webisa.webdatacommons.org/prov/247239797>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/219487282> .
<http://webisa.webdatacommons.org/219487282>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/219487282>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<docstoc.com> .