How many institutions are in Citizens Bank Building?
select count(*) from building as t1 join institution as t2 on t1.building_id = t2.building_id group by t1.building_id having t1.name = 'Citizens bank Building'
Generalize this process for all buildings.
select t1.name, count(*) from building as t1 join institution as t2 on t1.building_id = t2.building_id group by t1.building_id