How many times was episode 20 of the Law and Order series nominated for the Primetime Emmy Awards in 1999?
nominated refers to result = 'nominee'; the Law and Order series refers to series = 'Law and Order'; the Primetime Emmy Awards refers to organization = 'Primetime Emmy Awards'; in 1999 refers to year = 1999
SELECT COUNT(T2.award_id) FROM Episode AS T1 INNER JOIN Award AS T2 ON T1.episode_id = T2.episode_id WHERE T2.year = 1999 AND T2.result = 'Nominee' AND T1.episode = 20 AND T2.organization = 'Primetime Emmy Awards' AND T1.series = 'Law and Order'