About: http://webisa.webdatacommons.org/391181909

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Draw a reference mark on the bottom of the ring stand to indicate the rest position of the swinging pith ball without being subjected to any force other than gravity.
http://www.w3.org/ns/prov#wasQuotedFrom	education.com