you would Study because Interested. Population can be used for Study. Population is related to Measurement. Measurement is related to Time. 
Equipment is related to Card. Card is related to Celebration. 
Interested <--MotivatedByGoal-- Study <--UsedFor-- Population <--RelatedTo--> Measurement <--RelatedTo--> Time 
Equipment <--RelatedTo--> Card <--RelatedTo--> Celebration 