In restaurants with a review of 2, how many restaurants have a street number below 500?
review of 2 refers to review = 2; street number below 500 refers to street_num < 500
SELECT COUNT(T1.id_restaurant) FROM location AS T1 INNER JOIN generalinfo AS T2 ON T1.id_restaurant = T2.id_restaurant WHERE T2.review = 2 AND T1.street_num < 500