What are the first names of the faculty members playing both Canoeing and Kayaking?
select t1.lname 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 = 'Canoeing' intersect select t1.lname 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'