Question: What about Mountain Climbing and Kayaking?
SQL: SELECT T1.fname FROM Faculty AS T1 JOIN Faculty_participates_in AS T2 ON T1.facID   =   T2.facID JOIN activity AS T3 ON T2.actid   =   T2.actid WHERE T3.activity_name   =   'Mountain Climbing' INTERSECT SELECT T1.fname FROM Faculty AS T1 JOIN Faculty_participates_in AS T2 ON T1.facID   =   T2.facID JOIN activity AS T3 ON T2.actid   =   T2.actid WHERE T3.activity_name   =   'Kayaking'