How many reviews of businesses that are still open received an uber rating on the funny vote?
businesses that still open refers to active = 'true'; business received an uber rating on the funny vote refers to review_votes_funny = 'Uber'
SELECT COUNT(T1.business_id) FROM Business AS T1 INNER JOIN Reviews AS T2 ON T1.business_id = T2.business_id WHERE T2.review_votes_funny = 'Uber' AND T1.active = 'true'