Producer is a type of Cause. Producer is related to Speaker. 
Exercise is related to Building. you are likely to find Electricity in/at/on Building. Electricity is a synonym of Current. Current is related to Modern. 
Cause <--IsA-- Producer <--RelatedTo--> Speaker 
Exercise <--RelatedTo--> Building <--AtLocation-- Electricity <--Synonym--> Current <--RelatedTo--> Modern 