Well they want to be sure everyone knows the basics of it. Not everyone go to school in USA or Britain . For example, my school in Croatia did not even mention  matrices, mean, median and mode which are the basic things in US school system.####[['NULL', 'Mathematical_Related_Concept', 'NEU'], ['matrices', 'Mathematical_Related_Concept', 'NEU'], ['mean', 'Mathematical_Related_Concept', 'NEU'], ['median', 'Mathematical_Related_Concept', 'NEU'], ['mode', 'Mathematical_Related_Concept', 'NEU']]