Presence is related to Exist. Prevail is a type of Exist. 
Item is related to Price. Price is related to Oil. Oil is related to Thin. Thin is related to Page. 
Presence <--RelatedTo--> Exist <--IsA-- Prevail 
Item <--RelatedTo--> Price <--RelatedTo--> Oil <--RelatedTo--> Thin <--RelatedTo--> Page 