Improved is a form of Improve. Approve is etymologically related to Improve. Approve is a synonym of Consent. Consensus is etymologically related to Consent. 
Speed can be Dangerous. Speed is related to Rate. 
Improved --FormOf--> Improve <--EtymologicallyRelatedTo-- Approve <--Synonym--> Consent <--EtymologicallyRelatedTo-- Consensus 
Dangerous <--HasProperty-- Speed <--RelatedTo--> Rate 