Mercedes Benz repair: gas door lock, storage problem, negative cable

Question
How do I unlock gas. Dr if batery is dead

Answer
what model etc. Depending on if it is an older car open gas cap and pry off closing mechanism with a screwdriver. Disconnect your negative cable from battery before storage. Problem is with no model I cant really help you. Otherwise get in car and open up hood and get a new battery or charge it up at autozone