Arrival is related to Coming. Coming is related to Rise. Rise is the opposite of Lower. Lower is a synonym of Drop. 
Protection is related to Insurance. Insurance is related to Cover. Ridge is a type of Cover. 
Arrival <--RelatedTo--> Coming <--RelatedTo--> Rise <--Antonym--> Lower <--Synonym--> Drop 
Protection <--RelatedTo--> Insurance <--RelatedTo--> Cover <--IsA-- Ridge 