Slow Acceptance Hotspots

Uber's marketplace team wants to know where riders wait longest for a driver. trip_events logs a 'requested' event for every trip and an 'accepted' event when a driver accepts; trips that were never accepted have no 'accepted' event and are ignored. A trip is slow when more than 90 seconds pass between its requested and accepted events (exactly 90 seconds is not slow). Bucket slow trips by city and the hour of the request (0 to 23). Write an SQL query that returns the bucket or buckets with the most slow trips as city, request_hour and slow_trips. If several buckets tie for the most, return all of them. Order the results by city ascending.