Calm is a synonym of Steady. Steady is a synonym of Constant. Constant is the opposite of Variable. 
Narrow is a synonym of Specialize. Specialize is a type of Work. Work is a type of Operate. Cooperate is etymologically related to Operate. 
Calm <--Synonym--> Steady <--Synonym--> Constant <--Antonym--> Variable 
Narrow <--Synonym--> Specialize --IsA--> Work --IsA--> Operate <--EtymologicallyRelatedTo-- Cooperate 