Find the number of schools that have more than one donator whose donation amount is less than 8.5.
SELECT count(*) FROM (SELECT * FROM endowment WHERE amount  >  8.5 GROUP BY school_id HAVING count(*)  >  1)
number of schools = COUNT(*); more than one donator = HAVING COUNT(*) > 1; donation amount less than 8.5 = amount < 8.5;