Database: shipping
Question: What is the shipment ID of the heaviest shipment that Zachery Hicks transported?
SQL: SELECT T1.ship_id FROM shipment AS T1 INNER JOIN driver AS T2 ON T1.driver_id = T2.driver_id WHERE T2.first_name = 'Zachery' AND T2.last_name = 'Hicks' ORDER BY T1.weight DESC LIMIT 1