Income is related to Money. Money is related to Pay. Foot is a type of Pay. Foot is similar to Neck. 
Code is related to Law. Law is related to Degree. 
Income <--RelatedTo--> Money <--RelatedTo--> Pay <--IsA-- Foot <--SimilarTo--> Neck 
Code <--RelatedTo--> Law <--RelatedTo--> Degree 