Question: What is the maximum and minimum grade point of students who live in NYC?
SQL: SELECT max(T2.gradepoint) ,  min(T2.gradepoint) FROM ENROLLED_IN AS T1 JOIN GRADECONVERSION AS T2 JOIN STUDENT AS T3 ON T1.Grade  =  T2.lettergrade AND T1.StuID  =  T3.StuID WHERE T3.city_code  =  "NYC"